Hybridizing isn't "bad". Some feel it is unethical, but that's the only way I could see it as being "bad".
There are particular combinations of live bearers that will commonly cross and sometimes the lesser known combinations occur. I don't know the exact crosses, but I'm sure someone will say or you could Google it.
You have to keep in mind that these fish breed rather quickly and have lots of babies. So, you should under-stock or have homes for everyone. Or you could just do one sex for the entire tank.
55gPLANTED:Rainbows/Loaches/Garras|30gVIV:Crestie|20gL:Leos|10g:Pearl Fighter|5g:Betta|5gChi:Spark Gourami/Badis|5g:ADF|2.5g:Betta|2.5g:Betta|