Riposte heroes (+HP) - more effective with lower def
Low def heroes (+HP) - doesnt help since most of these heroes are high in offense or HP. That little def bonus wont help much.
High def heroes (+DEF) - these guys are already tough, just make them tougher
High HP heroes (+HP) - needless to say when they are combined with or already are good healers
Alot of healing goes by % so if a hero has high HP it would be best to maximize it (I am not talking about HoT)
My term for most of these talents are to maximize their strengths. Making something weak to becoming mediocre is still mediocre. Making something good to great is a better option in my opinion. Jackal for example, increase offense or defense? His low defense aint gonna make much of a difference by giving him 18 def points. I would just give him the 18 off points and make him an even better attacker.
Just my 2 cents. 