So I'm pretty sure different damage bonuses multiply together rather than just adding. For example, 10 points in int (1.50x more damage) and 10 in pyrokinetics (1.50x) multiply together to 2.25x more damage. Putting all those ability points in polymorph for more int would be just 20 int for 2x more damage. By late game, you'll do way more damage with a diversified damage source investment than with pure int (of course, polymorph is limited to 10 so you'll end up diversifying anyway).
Not positive, but fairly certain this is how it works and the numbers make sense. This is also what makes several damage bonuses so strong: e.g., 5 ranged + 5 hunstman + 5 fin = 1.25 x 1.35 (10% base + 5 hunstman) x 1.25 = 2.10x when attacking from high ground (much better than 1.85x from all points in fin).
Larian needs to make this much more clear.
