Loads of stuff TBH. But I think it's so personal and some people would hate these things.
Co-sleeping - yes. Gets you sleep (probably the most important) plus I just love snuggling them when they are so little, breathing in sync with them, it always feels like exactly the right place on Earth to be. There is something animal about it which I like. I have a co-sleeper cot and I've been lucky in that both of my kids most of the time have been fine in their own space in that if I feel I need more space too.
Excuse to sit down for ages :o
No washing up, sterilising, boiling kettles. I am really disorganised too so I appreciate not needing to panic due to running low on formula, or pre plan too much e.g. days out. Also formula is so expensive. We did a bit of formula this time and it was a pain trying to make sure the bottle wasn't too hot, too cold, too long made so bacteria was a concern, having to decide when it was time to throw it away and start again.
It is a magic sleep inducer. (Not always, but when it is)
You don't have to have a routine, or keep track of when you've fed them because you can't do it too much or too little (broadly) so you can just do it whenever they want or when your boobs feel full.
The love they get for it/games they play with it towards the end of the first year and beyond. So funny and cute. Squirting milk also funny.
You can put it on random skin complaints, loosen stuffy noses with it, use as eye bath for conjunctivitis.
You can keep going with it throughout the period when they're doing mad fussy eating and so not worry about their vitamin intake. Also immensely reassuring when they are ill, because it is so good against dehydration. I like the added reassurance that it gives antibodies to anything the family is exposed to as well.