Suggestion 1: add SHA-256 too, not only scrypt  
That's good because:

1. Sometimes to mine other sha256 altcoin could give you more profit ( like ZET, PPC, TRC, etc... ) than mining BTC directly.
2. Mining sha256 altcoins instead of BTC directly will have an indirect impact lowering the BTC difficulty, which I think is also beneficial.

Suggestion 2: Support LTC conversion too. You could modify the "password" behavior so the user can choose which coin to auto-convert to:
-p "btc"                -> the auto-switch will convert the alt-coins to BTC
-p "ltc"                 -> the auto-switch will convert the alt-coins to LTC

Pls !