This is pretty old, but I'll take a stab. There are three aspects of exploration you want to maximize, and they're often at cross interests:

1. How good am I at killing mobs?
2. How much much latitude does my RP grant me to kill mobs?
3. How much can I see and/or obtain without killing anything at all?

Healing gear is a big help when killing mobs and good-aligned warriors arguably have easier access to healing gear. Unfortunately, good-aligned warriors are also the most restricted in terms of role-play.

For #3 they're nice because you can request stuff without having to actually kill mobs. But they're not nice because they can't be duergar or wood-elf, i.e. two races that will allow you to notice some things you wouldn't otherwise notice. That being hidden and camouflaged mobs.

If you want to explore underwater then dwarf, felar and arial are obviously not good choices.

Most cabal powers are helpful to some degree. However, by joining a cabal you obligate yourself to participating in cabal wars, which can distract you from your exploring. Then again you get powers, and usually some built-in allies to explore with. Especially if you're new, having access to veterans who can walk you through some of the trickier areas can save a lot of time. That is, if you just want the info and not the enjoyment of figuring stuff out for yourself.