I have another ID I have started a team that got placed in the start of season season 4. I was able to pull in 4 good FA's and add about 2000 seats to start the season. Somehow, I finished 9th in the table that season and added about 5000 seats throughout the season. Now, the season just rolled into season 5 and I had almost $900,000 to play with for free agency. I signed 8 guys who were in their 50's or 60's and I can tell you I have a much better team starting season 5 now than this team I have in season 5 that just won the league in season 4. Oh, and I have $250,000 over for stadium upgrades.
I feel I have a real good shot at competing for the league title in my second season with my alternate ID team. So, at least through 5 seasons, taking over a team in midstream is not that difficult. Later down the road might be difficult but its not too hard to do it in 2 seasons.
Trust me, until there are more people that take this seriously, building a top of the table team is easy and can be done in 2 seasons, no problem.