GAH that Gucci bag is hideous, were the creative team just thinking, how can we make this bag even more ugly and more nonfunctional? Yes, let's add a weird leather strap around the handles.
TBF, Diana was a name associated with a Goddess well before a Princess came along, and a Goddess that's usually associated with hunting so it kind of makes sense with leather goods. I have a name that's often used to name clothes/accessories, I always feel like I'm supposed to buy them as a result..
WRT moths it's not so much the ones that fly around you need to worry about it's the eggs they lay on your woollens and then wake to a woolly meal. Keep things out in the sunlight occasionally if you can and I tend to stick everything in the freezer for a few days before storing in vacuum sealed bags when putting it away for winter.
Anyone trying to shed the Christmas kilos look away now, behold my French pastry ted talk for Sooverthemill (although ted talks are meant to be short, no, this is not going to be a short post).
Maison Aleph in the Marais, flavours of the levantine married with classic French pattiserie. Filo makes an abundant presence too and brings a bit of baklava flair. The star here is the pistacho strawberry tart, but the lemon tart is good too, they also do mini sizes so you can sample a few different flavours and wash it down with mint tea or an amazing lemonade in summer (although no one to stop you from having it in winter).
L'éclair de Génie, as the name suggests only sells éclairs. Now when it comes to chocolate eclairs I'm really traditional, I don't want it overly fancy with single source chocolate so I prefer the traditional boulangeries for that (like Gosselin or Carton below) so I tend to go for the special flavours, their salted caramel is the perfect balance, even if you're so burnt out by everything salted caramel this will have you believing why it was ever a good idea in the first place. Seasonal flavors are also worth a go, maple pecan, etc. They also do a selection of baby ones.
Philippe Contocini (who is a big old teddy bear) always had me yearning his Paris Brest, it is excellent but now I have a secret side piece in the buckwheat and confit lemon, the exotic temptress with a very unique flavour.
Pierre Hermé, for all his mastery with flavours and invention and superior macrons it's the classics that I love here. The lemon meringue tart is my favourite LMT in Paris and ditto for the Opera (it's called something else, it's square and it's chocolate, maybe it's even called chocolate square in French 😂). Lunch at his cafés is also well worth the trip.
Le Cheval Blanc (part of the hotel in La Samaritaine but open for non hotel guests) for the best croissants ever, and frustratingly pretty. Amazing the breakfast (just take the abundent breakfast menu, nothing else makes financial sense when tea or coffe are half the price and it's delicious) and a beautiful view over the Seine. Fine tarts can be had in the afternoon (or at the Louis Vuitton exhibition, same pastry chef).
Boulangerie Utopie, the sésame eclair, sounds and looks gross, is in fact delicious. Coffee eclair a close second and that's saying something as the coffe eclair is always the poor consolation prize in my book when a boulangerie has sold out its chocolate ones. Croissants, viennoiseries and bread are excellent here too.
Yann Couveur, a competitor for the Paris Brest of PC, they're both good in different ways (don't make me choose) and the Kouign Amman.
Du Pain et des Idees, for the best bread, Pain des Amis to be specific (which they serve at Hollybelly), the only downside is that it ruins you for any other bread 
There is a lot of hype for the pistacho escargot (pinwheel pastry in English, I think? It's a pain au raisin shape of the size of your face) and for once it's worthy. Although they often have seasonal variations, a raspberry and pink praline version I once had was particularly memorable (check they're not on holiday before going, they often disappear at odd times). Limited seating but you can stroll on to the Canal Saint Martin not far from there for proper French cinema vibes with your goodies.
Dunes Blanches Chez Pascal Paris, cream puffs meet chouquette unlike any other from the golden triangle near Bordeaux. I was unconvinced there could ever be something overly special about cream puffs but they were being served at an event I stumbled into once and these really are something else. Filled with cream but light as can be, also an interesting sweet/salt balance that reminds of the seaside (but maybe it's the beach inspired interior?) and plenty of interesting flavours available too, like Yuzu. There's something really special about the cream and it's a whole secret patented thing. Must be tasted to be understood, I was once skeptical too.
Mori Yoshida, Japanese pastry chef but that doesn't necessarily translate to traditional Japanese flavours or pastries (there are some) but rather it's that perfect Franco-Japanese marriage of striving for absolute perfection usually at the cost of oneself. People come for the Mont Blanc, but I adore the Fraisier, flawless croissants, chausson de pommes (fancy version of it anyhow, see Poilane below)
Poilane here I love the chausson de pommes for it's absolute messy exterior, that feels homemade. The corners of the bag twirled, greasing up the paper translucent instantly and it's just one of those simple things done absolutely right that can evoke childhood memories of a loved one feeding you and must be eaten within hours of coming out of the oven. All the taste without the airs with proper apple flavour. The punitons cookies are also a surprising hit here, far from a punishment as the name would suggest, ridiculously simple but perfectly imperfect nonetheless. Bonus points for keeping good for long. (Yes, the famous bread is great too, but it's no Pain des Amis, I'm ruined, I tell you, ruined).
If you've run out of time (or desperate for a pastry the moment you arrive) there's a bakery just outside Gare du Nord, Carton, that is your more traditional boulangerie but it is an excellent example of one where they take a lot of pride in what they make and prices are very reasonable. They won the best croissant in Paris last year or the year before that.
Aki Boulangerie (Japanese mentioned before) strawberry shortcake or melonpan, and the onigiri is great too.
Grand Cafe Tortoni inside L’Officine Universelle Buly 1803 (same people behind Cire Trudon), Marais location, it's a revival of a 19th century cafe, original interior and everything, prices on the wall still in Francs, although probably it was centimes 🤔 Beautiful little fruit tarts in summer, wild Italian strawberries, <weeps> madeleines are a good bet in winter but this is more of a hot drinks recommendation. It is not as frighteningly expensive as it appears (or as the Buly shop is) many come for the thick hot chocolate but (I'm not a coffee drinker but I do love the smell) I'm assured it's the best espresso around (my nose concurs) and it's at Italian prices, ie. bizarrely cheap. Tea is at weird inflated Paris prices but they serve proper matcha tea (also a rarity in Paris) but I usually go for a pot of mint tea.
Le Ritz Comptoir for surrealist takes on classic French pastries. The star of the show are the reinvented croissant/pain au chocolat but it sort of resembles puff pastry, so I always go for the seasonal fruit version of that as it's almost tart like. The madeleines are also delightful, not your average madeleine at all.
Mokonuts, little family cafe, the cookies are the attraction here. American style but with worldy flavors, think miso and tahini, often imitated all over Paris but none compare.
Tapisserie (related to the Septime restaurant), the maple tart gets all the admirers (too sweet for me) and the choux (lovely but no magical cream like Dunes Blanche). I rather love the feta and za'atar scone, which is more like an American scone, which are more like American buttermilk biscuits (which I also adore but difficult to get right outside the Southern US). The petit fours can be great too, I'm very tepid about their laminated dough pastries, have those elsewhere.
Faurn Boulangerie, very recently opened (like the earlier this month recently) affordable venture from a Michelin starred chef with Lebanese roots whose main restaurant marries those with French cooking in fine dining style. I came for the Man'ouche (also excellent) and was charmed by the babkas.
Bit of an odd suggestion for a Brit to have High Tea in Paris but the High Tea at the Hotel de Crillon is an experience (potential alternative suggestion for the anniversary celebration at Joël Robuchon). It's only really British if you squint, it's very much a French take on the concept with more creativity in the savory department, seems very popular with Japanese tourists for some reason.
Finally for fine chocolates, Jacques Genin for absolutely quality and amazing window displays and Patrick Roger for an absolute rock star take on chocolate. But, shh, the Belgians do fine chocolates better (and cheaper), Pierre Marcolini does have a shop in Paris (amazing ice cream in the summer time).
Final thoughts, do not go stand in line for hours at Cedric Grolet. For whatever reason Instagram made him very famous. All nice enough but not worth the wait if you're expecting anything earth shattering and scarily expensive to boot. Peter Kayser was once great but is a bit of a chain bakery now. Chain bakery Paul still makes an excellent sesame baguette though so not all bad 🤷