First, thanks !
1. Short answer, no.
Long answer : you have the possibility to change the sprites, but it's a titanic work. If you're a good pixel artist, count around 1 month to do it, I guess...
2. Same answer, you'd have to change the sprite, which would need a short week, in best case, I guess.
In TE2007, it'll be possible to paint the skin of the player so you could make him look like a famous player, and the game will have both single and double-handed backhand. But TE2007 won't be there before long time (not before June 2007, I guess...)