Until you receive 5% as bonus for fans attendanceIs not so far to find the right price for the tickets but this depends a lot from a team to another because not all the teams won the same number of games and trophies so not all have the same number of fans. Set a lower or decent value for your level then go +1 or -1$ to adjust until you find the perfect balance which will give you full number of fans at game and full bonus.
Regarding win bonus, the more the better as long as you afford.