I think all you need is a quality engine, not one of those that suck air from everywhere so it does not run properly.

My own preference is for the 2-strokes; cheaper, easy to run, less maintenance and so on...

If money is not an issue, 4-strokes are very good choices as long as they are good quality. I just purchased a used YS 140 DZ (was really cheap) and LOVE the incredible throttle transition and power.

A 2-stroke is often about half the price of a 4-stroke of comparable power.

In my opinion, the aircraft has more to do with 3D than the engine, as long as it is powerful enough.