I've been running an unusual ATOW campaign for nearly two calendar years now. I was expecting to do a realistic, so-gritty-you-could-die-everytime-you-screw-up campaign. About seven calendar months into it, my players asked if we could make it more space opera and less space realism. I deferred to their judgement to make it more fun for them (it still took until April this year before they saw the inside of a 'Mech. But it's been a hella ride for them since).
The Campaign started 3019 on Galatea. All PCs began as members of the Dispossessed for their own reasons (a disgraced alcoholic of House Kurita, a highly skilled triple agent on the run from Loki, SAFE, and now the ISF, A Tortugan concealing his identity from the Suns player whose family he had killed years ago in a raid on the Outback,etc. All players were working for a local crime lord whose big plan was to get spaceborne and to take over a jumpship from within. Piracy, in other words. Their goal was to get behind the controls of a Mech again and feel the prestige and power from sitting behind the controls again. Even so, everybody has at least one backup character in game. There are three players juggling two characters because they did something in the past that incapacitated their primary guy.
The style we've used throughout has been pretty free-form. We don't spend a lot of time rolling dice, preferring to roleplay it out. They've been catching on to my style of GMing, which is generally based on the players making things happen instead of the whole stimulus, response, stimulus bit. Their enjoyment and mine has risen accordingly. I get to manage their innate creativity instead of forcing change on them. Of course, for a few of them, this is their first exposure to the BattleTech Universe. The two girls who joined the core group in March have become steady fans of the RPG and TW game.
It is now nearing the end of 3022 and my players have become a major focal point in the 'Sphere after finding and fighting over a lostech cache of six operational Thunder Hawks.