I've beaten the game multiple times on Hard using hybrids. The amount of tactics Larian offered us to use for fights is tremendous.
What area of the game are you having problems with? I'd be glad to help you. Maybe post in the hints and tips section.
Which hybrid?
A real hybrid has to split attributes, such as int/str rather than a pure who can use int/con.
It just seems vastly sub par compared to a pure, not hard. I really wanted to make a 2H + Lightning user but either my spells will suffer or my melee will unless I forgo con and speed. In other words I'm building a lesser hero just for flavor.