Well, he reads all topics, he surely will read this, but i don't know if it is POSSIBLE to do it, maybe manutoo wants to do it, but the engine of the game doesn't support something like that...
Nice ideas, i remember there was ''Mario Game''with all this things, with an area in which you practice volley, in other serve, in other return, etc But, i find hard, this can be done in Tennis Elbow.... you should ask manuTOO (game creator) Regards