I was at Target Field 4/20 and didn't notice any problems as far as lines go for the men's restroom. I didn't realize until after I'd finished there was an additional set of urinals in part II of the room, but I didn't have a line to wait it in. I was in and out in and back to my seat in less than a 1/3 of an inning. Before the game might be an issue as people are slow to get to their seats.
I think I would prefer to see Joba in the bullpen as well. He can pitch the 7th and 8th and eventually replace Rivera. For as much as they talk about Rivera being irreplaceable, they're not going to appreciate him until he's gone.