I rest when I feel it makes sense from a rp perspective. This usually means 6-10 LR for the current content. If everything was further apart on the map, it might feel like I should rest more often (except for tadpole urgency) and if we had day/night cycle it would make it much easier to determine when to rest.
Yes, it probably depends a lot on which class you play. I play casters, and I would never have the goal to rest as little as possible. It would make combat very boring to me.
Do you use up your spells as soon as possible in a fight? I play a caster heavy party (custom is sorcerer, ranger, rogue, and wizard but occasionally cleric) and often find myself with spell slots left when I rest, especially on the pure casters. I tend to save spell slots for the "oh crap" moments and to set up chokepoints and debuffs rather than to do actual damage. Spike Growth, Web, Grease, and Cloud of daggers are usually my most used spells, and flaming arrows/Firebolt to help the first 3 of those along once the enemies are clumped up.
