I, too, am hating that they got rid of being able to increase the size of 4.0's ridiculously small text bubbles.
I was hoping that they might have fixed this issue with 4.1 today but nope.. this is really annoying and I don't see why they got rid of being able to manually increase it.

P.S.
You didn't hafta plug in a mouse, you were able to use the virtual mouse in-game by holding L1 and pressing R3. Once up, you held R2 on the text bubble and used L2 to change it.
Just an FYI incase they add it back in.