Re: the seatbelt, I have a Clippasafe bump belt, which is quite comfortable (before I got it, I was feeling a bit faint with the seat belt up higher). It holds the lap belt across your lap, so the cross-body strap is still there to prevent you from going flying in an impact.
Tyelperion, sleepsuits are great for the first couple of months. Our babies, being winter ones, are going to spend a lot of time tucked into cosy-toes (in the pram) or snowsuits or the like! And they always get socks off! They're not quite so good at it in the early stages, but by the time DS was about 3mo, he was frequently "praying" with his feet, prayers which were evidently so powerful, they knocked his socks off! 
I've got a list of snowsuit, buggy board (for DS), moses basket mattress and something else I can't quite remember, but am trying to remember to leave my DM and DMIL something to buy, as they might be a bt cross if they don't get that chance (or buy something dreadful...
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