Hmmm- tough one.
1- Change mat - planned to put it on a table, but ended up using the couch when she was little and now the floor. I use it, but don't need it, a towel would do to catch accidents.
2 - Good clothes - had to many at one stage and not enough at home cloths, really just need 2 sets and 1 semi good one as back up in the nappy bag
3 - Fancy bedding - as has been said before what is the use of the pillow case? Mainly use sleeping bags/suits here, so top sheets etc aren't that much use.

I do use a baby bath, we have no big bath and the laundry/kitchen sinks were too cold for a winter baby. Only time we did not use it was when Maggie was too long for it, but was not yet sitting (we showered with her). We used it again once she was sitting really well by herself.

For toys rather than bottles I use the little specimen jars (unused of course). Hundreds and thousands work really well in them and they are small enough for bubs to hold