Well, on the left side of your TX, you will find a lever. This lever controls throttle as well as rudder.
Just pulling your leg. The fact is that you rarely can have too much power and you have a throttle and should use it to govern how much power you want. Rarely does anyone fly with full power these days. They go for big engines and use full power for verticals or to get out of trouble. The rest of the time they are back to half throttle or so.

So go for the biggest, the meanest and snarliest engine you can squeeze in. And use your throttle to control that beast. There is nothing more frustrating than flying a model that is borderline powered and nothing more satisfying than flying a model that has reserve power to get out of trouble.

So go for the most powerful engine is my vote.

3dbob