1, i'd go thief [assassin] Sorcerer [dragonblood] 8 / 4 or 4/ 8
2 yes if you use magic to hide / turn invis, drop a fog etc
3 in general dex is more useful than str because it also helps defence... which is why drogon armour and the shield is so invincible
4 yes dual weild is king because [1] things that increase weapon damage such as dipping or magic rings do it to both weapons & [2] sneak attack can trigger on both weapons (but only once)
example your assassin / dragonblood has two shortswords a ring of +2 acid damage, dips them in fire and runs upto a monster... her first attack misses but the off hand attack hits
popup - sneakattack = yes pleae and results in weapon + fire + acid + sneak... perhaps you also have lightning charges to add in but we get the basic idea
p.s, any option that gives advanage is well worth your time to encourage
