1) Despite agreeing that ranged combat is maybe a little too good, I do find it odd that people say they don't bother to keep track of ammo, but then also complain that it's too easy for a ranged combatant to fire multiple shots per turn. To some extent, this has started to make me think "yeah, casting a bunch of spells is really easy if you don't keep track of spell slots."
A valid comparison, really. If you're willing to apply in-narrative pressure to prevent frequent re-charging of a resource, and don't mind the bookkeeping burden of tracking the resource, a sufficient limit on the availability of that resource can 'balance' it.
Spell slots recharge with a long rest, you don't need to be in town or have specific materials available, you just rest and you have them back. Ammunition recharges with the expenditure of fairly trivial funds, in a place where it's available to buy, or, presumably, by making a survival or artisan (boyer/fletcher - there's precedent it goes back to 1e secondary skills!) check when the appropriate materials (reasonably straight sticks, feathers, metal points or flint) are available. The latter's probably /more/ situational than the former, so less suitable as a balancing factor.
2) It is actually fairly easy to carry a lot of ammo.
And cheap to buy. IIRC, the option to track ammo includes recovering ammo after a combat, too (it did back in the day, anyhow, and there's nothing unreasonable about it - what do you care if the next guy you shoot gets the goblin version of hep-C?).
Besides, not tracking ammo, like not tracking encumbrance, polishes 5e's 'rules lite' veneer.