That's grouse to hear the HAB's are nice and supportive for older bubs - maybe I heard that from someone who wanted to babywear an even older bub, or from someone with a heavier bub.

Hey Lime, do you know why Charlie didn't like the Babyrock carrier? I know River hated pouches/slings as a bub - perhaps because I wasn't confident, but I think moreso because he just preferred to be carried upright - even holding him in my arms cradle style he would fidget til I held him against my chest. But he loved carriers where he could be held upright - perhaps if you look at how Charlie usually likes to be carried will give you some clues as to what style of carrier to be looking for?
As for being too big for one - you have plenty of time!