Implement a challenge system, MLB

[Reffing Rev.]

I don't mind 20 challenges a game if the umps are having a bad night, but I like something I read somewhere: 1 wrong challenge = ejection and no more challenges that night.

If I were king of baseball this would be my challengeable play list.
--Home Runs
--Catch/No Catch (If a catch on a fair ball is overturned batter awarded 1B and all other runners advance 1 base from time of 'catch', if no-catch is overturned, batter is out - play by an infielder, all runners return to base occupied at time of pitch/play by an outfielder, all runners advance 1 base from time of pitch [this is assuming that a diving outfielder, or one against a wall is most likely not going to throw anybody out, a stretch sometimes, but ya gotta do something])
--Missed Base
--Leaving early on a tag
--HBP or not
--INT/OBS (if not called)
--Fan Interference (if not called)
--Safe/Out on last play of game (or potentially last play of game)
--Administrative type of events, batting out of order/4-outs, lost count, etc.

I would not allow challenges on ball/strikes, fair/foul or check swings.
The only safe/out call challengable would be the one that may or may not end the game.