I might limit the number of foul balls a batter can hit unitl he's called out. Once in a while it's high drama, but for the most part all the at bats that are extended endlessly by intentionally fouling off pitches get really tedious. Yes, in some cases it's not intentional, it's due to great pitching, but it seems pretty obvious much of it is intentional.
https://sports.yahoo.com/study-says-...170825013.html