MTS is actually when you run multiple tanks (stemming from wanting too many fish, of course!).
What do you mean by you have cycled the tank? Using the average Local Fish Store definition (that you've dechlorinated your water and allowed it to sit in the tank for 12-24 hours), your tank is not actually cycled. I recommend reading this article on
fishless cycling, and this article on the
nitrogen cycle.
Once you've read those and while you're waiting for your cycle to complete, you can plan your tank! Are there any fish in particular that you really would like to have? Starting with one type of fish you want and going from there is pretty helpful
Have fun!

I've been on here for the last five weeks or so while waiting for our tank to finish, we're antsy for fish, too!
Oh! And finally, here's a tool you can use to help plan your tank's stocking!
AqAdvisor - Intelligent Freshwater Tropical Fish Aquarium Stocking Calculator and Aquarium Tank/Filter Advisor