Buffet food to prep in advance

[hairycabbage]

I'm catering for about 25 in January and am stuck for ideas that I can prep in advance and freeze until the day. I have no objections to buying a load of party food from Tesco but it's for a special birthday so would like some yummy home made bits too. It definitely has to be finger food so no curry/ chilli etc (that would be so much easier, I know!)
I have a couple of hours on the day to stick stuff on the oven/ chop crudités etc but if anyone has any sweet and savoury suggestions that freeze well I'd be extremely grateful

Sausage rolls - I often make these about half the size of the ones pictures for DC’s lunchboxes.
Salmon and cream cheese quiches - 2/3 cup heavy cream is 160g double cream
Sticky hoisin sausages
Caprese skewers
Cornbread squares

Would you consider doing baps with a slow cooked meat, not too wet and saucy so it isn't messy? Most of these sorts of dishes freeze really well.

Samosas

Cookie dough, most biscuit dough in fact, freezes really really well. I would recommend you freeze in balls so all you need to do is place them on a baking sheet and bake, you can even do this from frozen for some recipes - Cupcake Jemma cookie recipes actually recommend this.