That's a million dollar question isn't it?
The only "good gene" that I can say is priceless is enchi... Color and pattern changer... A lot still left to do.. Quite a few people are working with them, but I don't care. Their combos are sick, and I want one! Or 5..
Some people can't tell the difference between enchis and normals... The enchi combos are definitely different.
I suggest you think of a cool project. Look at how you can produce that combo, and go for it. Buy the ingredients and just do it.