You only need one regeneration. Add more if you are cheap and impatient. (So cheap that you don't buy bonemeal potions)
Keep getting increased fortitude as soon as you can. It is the most overpowered skill.
As soon as you can get combat speed! Get both points! It is very useful! It increases your ap from 10 ot 11 then to 12! That means extra attacks!
All the other stuff is choice. If it suits your play style, Get it!