I was on my Mastermind the other day and wanted to make a team. She was level 45 at the time and I put out a message saying "Level 45 team forming, all levels welcome, but must have a travel power". I got some surprised /tells from people asking if I really meant all levels welcome, and I ended up with a team of really wide range of levels. I had a couple under ten, some in the 20's and a couple closer to my level. We had a blast and the low levels (both of whom were new to the game) saw zones and enemies like PI and Carnival of shadows they hadn't experienced before. It didn't matter what their DPS was, or their power sets, or their slotting, we just ran a few missions and had a really fun evening. To me the game is for playing and enjoying, not for worrying about the right power sets, level or slots. Yes there are times when it's best to try to stick to people of a particular power level, but apart from a particularly difficult AV which needs a certain amount of damage and control, it doesn't matter that much whether someone is sidekicked 20 or 30 levels up. I've been the only tank in a team with 7 controllers. I might as well have stayed by the door checking Facebook as everything was locked down and DoT to death before I finished entering the room. All I was good for was herding enemies into a group so the controllers could get them all in one go. No AT or power set is better than another. If you know your powers you are going to be useful to the team and have a good time. If you are on a team where someone is more concerned with DPS and whether you have the fashionable IO sets than having fun then leave and find another team.