Larger health potions provide significantly better HP per weight, unless you're throwing the vial away (in which case it becomes a much smaller advantage).
To make hunts last as long as possible, use Soft Boots plus Life Rings or Rings of Healing as well as potions. Doing this will mean you need to use less potions, meaning you need to take less potions, which (as shown above) are significantly less capacitarily economical (worse HP regain for your cap).
For most players, there will be a need for balance.
Using Soft Boots (if you own them) is almost a given considering that they're best for capacity-per-HP AND excellent money-per-HP (which can only be bettered with Terran Rainbow Shield or Life Rings, and even then only when bought very cheaply from players).
Rings of Healing at the shop rate are too expensive to be justified by most players (since they're far less economical monetarily) and considering their capacity-per-HP is so close, the cheaper Life Ring is probably a better option for most people.