Ok, then what I would suggest is this:
Your DH is caring for DS from 9pm - 12am. That's only the length between a feed anyway if DS is feeding every 2-3 hours.
If you're doing every night feed from 1am, then why not either do alternate feeds (eg you do 1am, DH does 4am) and then you both share the burden at night. Alternatively, you could take turns doing a night each (eg you do Monday, DH does Tuesday and so on) and then you both get a full night's sleep each. Just because you are on maternity leave doesn't mean you don't need to sleep :)
At least if you're a bit more rested, it can help you see the wood for the trees and you might be able to work out whether there is something to sort out re DS's feeding times, or whether he's actually being a normal 8 week old baby. I think it's too early to be thinking he's waking out of habit - he's still little enough to need feeding at VERY frequent intervals.
You can't overfeed a breastfed baby, but with a bottle you can. Babies are not meant to be skinny though, many are chubby and as along as he's not leaping up and down the centile charts I wouldn't worry about that.
Little babies grunt anyway when they're lying down and sleeping, so it might be that he's doing that rather than needing to be winded, in which case you trying to bring up wind might not be what he needs - he might just be a noisy one!
DD's feeds when she was tiny could take half an hour or more so again, it's not necessarily a problem that needs to be sorted. Have you tried going up a teat size? The milk flows more easily out of a larger sized teat (most bottles start on a size 1 or newborn teat, then go up to a size 2 or whatever) and that did make a difference to the length of feeds (still long though!)
Just my two pence worth anyway :)