OK, I agree, unfair to running-centric teams. How about this:
Team that gets the ball first in OT starts with the ball at their own 25. If they score a TD, they MUST kick the PAT for 1 point. Going for 2 not allowed. Team that gets the ball second in OT starts with the ball at their own 25. If they score a TD, they MUST go for 2 points. Kicking for 1 point not allowed. If you're tied because neither team scored, both got FG, or both got TD but missed their respective extra points, then in regular season games it ends in a tie and in playoff games you repeat.