I live in Germany, near the Black Forest. Generally love it but would be happier if I was working and we could afford to go home 2x per year. Currently we are struggling to afford to go home once a year and that is our only "holiday" which is fine for me, but disappointing for DH who is desperate to go on an actual holiday (which we have managed once in 12 years, and that was 6 years ago)
Pros:
Good school system (if your DC have fairly standard school needs)
Beautiful nature that you can access easily
So many lovely parks for children
Concept of "Vereine" - kind of a non-religious community group thing usually arranged around a hobby (gardening, music, sport, whatever is your thing there will usually be one) very welcoming to strangers and a good way to make friends.
Good expat network (this may be different in different areas)
Large houses/flats are more standard than the UK
Brilliant selection of cheap, accessible activities for children, especially things like school holiday clubs.
Cycling is very popular and accessible. Secondary pupils commonly cycle to school.
The culture of cleverness = nerd isn't really a thing here. It's not social suicide for boys to do well in school, especially in Gymnasium.
Also much less culture of binge drinking. It happens, but it's not the only social activity for teenage boys.
Independence for children, children treated with respect in terms of being considered people in their own right.
It is easy, close and cheap enough to come to the UK regularly compared to some other places, especially with only one child.
Uni very cheap (if you qualify)
Excellent public transport. Often free/reduced for school pupils.
Childcare of a high quality and well subsidised
Excellent maternity leave
Good culture for staying home from work if sick, including paid time off to look after sick DC
Dentists have availability and are mostly covered by insurance (some things aren't)
Health system works well and can usually get non-urgent appointments within 2-3 months. Health insurance is affordable (scaled to wage) treatments are generally high quality. Mental health care a bit more patchy but if you can get in, the quality is very high.
Weather is better. Real seasons. It's hot in summer with some great thunderstorms, snows in winter, spring smells incredible and is warm and pleasant. October is beautiful and colourful and misty and pleasantly chilly.
They don't seem to care about fashion
Suits me because I don't feel completely out of place.
I like the directness, most of the time.
Wages are high compared to the UK. Even for menial jobs the minimum wage is about €12 an hour. There's also a nice system called mini-job which is an income limit under which you can do whatever you like - don't need to declare this income for benefits, tax, etc. That's about €520 now I think (it's just gone up) so it's great for students, mums on maternity leave, starting out as self employed etc.
I love their attitude to raising kids in general, very gentle, relaxed, but also natural, outdoorsy, healthy.
Employee rights excellent, tenant rights excellent
Cons
The supermarkets suck. I can't get used to them at all. Apparently German people go to 2-3 supermarkets per week but I HATE this and just want to go to one place. Hardly any of them deliver and the delivery services are crap compared to the UK. Limited selection of food and the quality is mediocre. Meat is always pumped full of water. Hardly any ready meals or convenience foods like pre-made jar sauces. I don't mind the rush at the checkout to pack though.
Dearth of good-quality cheap stuff like you find in the UK. Here, if it's cheap it's usually shit quality. There are exceptions like the middle aisle of Aldi stuff, and IKEA for furniture. But generally if you want something not cheaply made you have to pay more. Especially toys, clothes, books and homeware. The cheap children's clothes are just weird, like something you'd find on a market stall in 1995.
I can't get my head into some aspects of German culture, it works for them but it just feels unbearably clunky to me. They seem to have this attitude of build something extremely well and then don't bother to touch it for 40+ years because it was so well made it works fine. Consequently great swathes of things feel like you're in a weird time warp from the 80s or 90s even though other things are modern, which is really confusing. Especially when you come back to the UK and everything has moved on rather than just weirdly-specific things that needed an update (e.g. before corona, almost everything was cash only and if they took cards, it was a Germany-specific style of debit card, hardly ever credit card. Now suddenly everything is contactless. They will probably not update this technology for another 40 years because it's done now.)
Schools - it's more complicated. If your DS is in year 5 they are equivalent to the final year of primary school here. The problem is that secondary is split into three "tiers" depending on how academic you are, which are Werkrealschule (practical, work based, not academic), Realschule (standard) or Gymnasium (similar to grammar schools). There are also Gemeinschaftchule which is where you can achieve any of the three possible school-leaving certificates but it's not quite as simple as that because this type of school has gained popularity since Werkrealschule have lost them, so most of them are converted from old Werkrealschule and the local attitudes reflect that, which tends to have a knock on effect on the pupil and staff intake. The school system is confusing TBH and hard to navigate as a foreigner. Teachers don't really have any contact with parents because they don't want to - their relationship is with the student. If your DC does not fit the standard mould (e.g. SEN) they may struggle to fit into the school system and there is not really accommodation except for severe disabilities. Home schooling is not allowed. But despite all this it DOES seem to work well if your DC doesn't have significant issues. My eldest has ADHD (no behavioural issues) and fits into school fine. However some friends have struggled with their DC who are more behaviourally challenging or socially awkward.
Language. I wanted to immerse myself and get fluent but it doesn't actually matter how fluent you are, speaking another language is exhausting 
Property is insanely expensive, including renting, although this is a worldwide issue. Wasn't the case when we moved here initially.
Don't like shops being closed on Sunday. It's shit for retail work because everyone has to work Saturdays (and they all believe absolutely strongly that opening Sunday would be even worse for retail workers because they can't conceive of the idea of weekday vs weekend workers!) and it's crap for grocery shopping because you only have one day you can reasonably do it.
It's hard to get a job because everyone expects a kind of qualification for this very specific role. People tend to stay in companies a long time, but that makes it hard to break in.
There are probably more things on both sides, but this is long enough so I'll leave it here! I do love living in Germany, I just miss home as well, and find some aspects frustrating but this may be just me as I have probably not studied the language enough plus have a bit of a dodgy education history which doesn't translate well.