I have my own global edit and personal edit setup that is pretty much the same as what I used in my 2k6 roster. You should download that one for now and play a few games with it to see if you like it. Gameplay wise, the only thing that bugs me is that its easy for me to get sacks. Otherwise, I dont have any problems. A lot of people talk about getting a lot of INT's but I usually average one or so a game defensively which is realistic. Some teams dont get a lot of INT's because their CB's and / or Safeties suck compared to other teams. I will say this though, I have all DB's (CB, SS and FS) globally edited at 40 for catching and secure ball because quite honestly, I hate it when I or the CPU should have an easy INT but then drops the ball. That drove me nuts but with my setup, it rarely happens. As for the human player, I will throw a high amount of INT's in a season but that's because I prefer passing over running especially if my QB / WR combo is awesome compared to my RB. Just try out my old roster if you want to check out how it plays.
I know some people have also complained about the lack of Yards After the Catch (YAC) but I think that has to do more with who you're playing with and who the QB / WR's are as well as who your playing against. Using my 2k6 roster file, I remember playing with the Colts against the Browns and I passed for over 500 yards and like 8 or so TD's with Manning. Manning, Harrison and Wayne were pretty much unstoppable. But when I played against the Patriots, it was a struggle that I think I lost if I remember correctly. I think it has more to do with the team you're playing with, who's on your team and what team you're playing against and who's on their team defensively.
The franchise files usually already have the schedule, correct NFL salary cap and other stuff already in place so the user doesnt have to do it. I'll be posting a roster and franchise file in September that already has everything in place.
And yes, it's usually setup to where all 32 teams are user controlled but that can be changed at will.
Hope this helps.