vests [value range] from boots, matalan, same for sleepsuits, sleepbag from asda, matalan.I would tend to buy the cheaper ones and at the right size probably 6-10 in each size, i change am&pm.
Milton to soak messy clothes and to sterilise dummies,bottles,nipple shells. Milton is the only liquid solution you don't need to rinse off, honest almost no taste, use a large container/jug to sterilise equipment.
a heartbeat/white noise sound box.
swing seat, the small easy to move type,rather than a vibro-bouncy seat.
pillowcases as sheets in basket or normal cot sheets folded down.
LOTS of muslins, i tend to buy white and add a dylon dye to give me a personal colour ie orange, purple.
Small velcro terry bibs again cheap and lots, tending to use a new one very regularly with a sicky baby.
a snuggly soft toy for baby to cuddle get 2 if baby takes to it or regularly wash and alternate different ones.
a sling, i prefere the ring slings as baby can recline. try this site
Infant seat, the are heavy empty so would go for a stage 0-1 seat that can be fitted into car rearward facing for now and at the appropriate time for childs weight be turned to forward facing, so 1 seat from birth to 4y.easy to see car seat guide
You will get toys and clothes as gifts.
Not to be down on bfeeding as believe it is great, but get in a pack of steri bottles just in case, in the past i have opened the wrapping and with a sharp knife cut off the 4 locking bits and reused the bottles after sterilising in cold water and milton for many months, handy if others can feed baby EBM, £1.99 for 4 125/250ml size.