As for Q2 leads to Q3, which Hobbun put foreword. Basically, which classes can turn into what.

I was planning to have a the following:

Knight to Paladin - someone said a Paladin was an result in another post Thief to Archer - answered by you Paladin to Cleric - ? Druid to Sorcerer - ?

I picked these for strictly nerd reasons. However, if you could tell me they work or not; then I would know if I had to start over.