Need help with my heroes

I have been playing about a month or so and I have been lucky during the weekend to draw some good characters. I actually do not know how to set them up properly to take advantage of their skills.
Bellow is my list.
If any experienced player can guide me I woul highly appreciate it.
What to focus on first?
Which are better for over and PvP?
Stuff like that.

Thanks in advance.