I've done a bit of everything, so this is my take including what I do at my large vs. home tourneys to make it more fair.
Large events - example MAGfest PAPA circuit event - I don't play in order to focus on ensuring everything runs correctly. No way I would have had any fun either if I tried to qualify - considering I worked 16 hour days 3 days in a row, I'd rather have been sleeping than qualifying. But if a manager does play, then it requires additional managers on duty, and a rules official to make any ruling the player/manager is in involved in. The player/manager cannot make rulings on a game he/she is involved in. Also, ensure any scorekeeping s/w doesn't allow the player/manager from editing or entering scores for themselves (neverdrains does a good job with this).
Smaller events/house events - In most cases, if a player is going to go through the effort to host a tourney at his/her own house, then they should be expected to play. Otherwise, why would they put it on? In some cases, the same goes for putting on a very large tournament - if they go through all that effort, then they should be rewarded by being allowed to compete.
Some things that can be done to minimize home field advantage or playing in larger tournaments:
1) Ensure the game list is available so players can learn the games ahead of time.
2) Consider bowing out of any cash winnings. I don't pay to play anymore and I don't receive any winnings from my house tourneys. The comp is only $20 and most players consider $2 / hour to get everything ready a fair trade off.
3) Wax, re-level, tweak the machines the days leading up to your tourney, test the games but then don't practice. This always negatively affects me as the games all play very differently than how I expect. Especially a good Novus 1/2 on the playfield, it becomes faster, enough that I don't know where to expect the bounces, extra speed, and even shots are off a little when the ball is on the fly. Definitely evens the playing field enough to make a difference. And allow players to practice for at least an hour, maybe two before the tournament. Now they have the shots dialed in and the host doesn't.
As for running IFPA states at a house, it's preferred by most players in my area because the collection and quality of the games is generally better than location games. Malfunctions are also easier to deal with where on public locations if you don't have the operator there, even a simple stuck ball can have a negative impact to the players. We rotated to another player's house last year and even that worked out great as the collection played hard but fair and was far better than most routed games. Having said that, some of the locations' quality of machines are way better now and we'll likely consider that for 2017-18.