Don't put a shrimp in your tank, just using cured live rock is perfect. Actually, the smaller the cycle you have, the better, as each cycle ends with excess nitrate in your water. I'd get the lights going a few hours/day if you're adding live rock that has coralline algae (the purple stuff) because you don't want that to die as well.

You should definitely add a sump if you can. It will give you much more flexibility in choosing a skimmer, simplify top-off and Ca/Alk supplementation, and increase your water volume and gas exchange. A canister filter that contains mechanical filter media is not good for a reef tank; it will take micro-fauna out of the water column that is very beneficial to keeping corals.

To me, watching all the new life emerge from live rock is one of the best parts of setting up a new tank. Have fun, but watch out for flatworms!