Question 1: What was the maximum level you reached during Alpha?
25
Question 2: What level did you have the most trouble with leveling above or did leveling become more difficult?
At 23, quests became scarce, even repeatable ones, so getting higher than 23 seemed like a real chore.
Question 3: What are about a few "important" levels that really opened the game up or had really interesting content?
15, 17, 20 were all cool levels where different things open up.
Question 4: If you ever made an alternate character, at what level did you stop leveling them up at?
Well, I was going to level a Whipper, as soon as I got my Punisher to 29.... that didn't happen.