Lowering on 19's might indeed make you Crackers!

Sure to experience issues going down that route, plus the old speedo will become inaccurate.
18's appears to be the best compromise, and does look the best. Then add some lowering Springs at least, or do it properly and add a nice coilover kit to complete to look.
Springs - Eibach Sportlines on 18's popular with members here.
Coilovers - Errm, not sure who's best at the moment, although I'm sure someone will clarify shortly!