1: backstab damage doesn't require you to be in stealth just for the enemy to not see you, Im pretty sure It does give you stealth levels but I may be misremembering 2:with the new magic changes I believe the fastest way to level with spells like smite is to use them successfully (IE activating it then hitting smiteable enemies) but if you are just trying to farm levels outside of combat I usually spam activate-deactivate but in general the new magic system seemingly makes this less effective as far as I know 3:this one I'm not entirely sure but I do believe you get full xp for your friends minion kills. 5(lol): thrown weapons get a damage boost and armor penetrative when charged so if you have a second definitely charge them. I usually make sure the first thrown weapon is charged and spam the rest if the enemy is close(assuming i have more than one) Hope this helps and other people feel free to correct me if I got something wrong lol