Lot's of good ideas here. Maybe max 2 timeouts for 3 minutes to use however the player wants. TV advertising would like it.
Or, a point penalty could be a good idea too.
Also, as someone mentioned, allowing the opponent to receive coaching advice while the player received MTO has merit.
But, yes, something needs to be done to curb the abuse. I like a point penalty. Maybe point penalty on the 1st MTO and point penalty and coaching for opponent on the 2nd MTO.