Shattered Kingdoms

I would recommend basically following the people who don't seem to roleplay much that look like they know what they're doing. You'll figure out where and how to get XP then. What's more important, in my opinion, than bringing in big XP is bringing in consistent XP. If you can mindlessly fight something and get low-risk XP gains, it's easy to just level up in the background while you do something more interesting in the foreground like trolling the forums, watching a movie, or enjoying the finer things in life.

That being said, the tactics of leveling involve mitigating risk for creatures that, under normal conditions, would be perilous to you. Casters mostly do this through things like positioning and leveraging weaknesses of one sort or another. I will warn you right now, do not try to cast for xp in group with a melee fighter. You're just being taken advantage of for your familiarity and group bonuses if someone is quickly killing things with melee damage with you in the group.

As for detecting aura, it is no great secret that there are items in the game which refuse to stay in the inventory of non-aligned folks, and certain commands provide different results based on the combination of your and the target's alignment. Perhaps these might have some manner of practical application. Beyond that, I believe journeyman priests have access to know alignment, do they not? Detect aura is around there, too.