Zalmi, It sounds like a pretty good first try. After 30 years using two mics and a tiny Shure line mixer, I now have 3 new AT choir mics, two At Pro-4's, two channels for my digital piano and in/outs for tape and CD. All this goes with a long-awaited PA system too. The first few weeks were trial and error to get the mixes and balances, but now everything seems just great. I'm sure you too will get everything just perfect very soon. Good luck.
Cass