I don't like the clock, but the visit limits are okay. However, if you're going to limit timeouts for the catcher to go visit the mound, then limit them for the batter as well. If the catcher can only go to the mound once per inning, then all batters should only get to call time to step out of the box once per inning. To be more fair, I'd say one mound visit per batter, and limit it to 10 seconds, once out of the box per batter, and once off the rubber for the pitcher.