Yes heres another point.

Power is not everything for example, well it IS but take a look at this:

Take two identical funflies, one is powered by a 36 size engine the other is powered by a 46 size engine. The 46 size engine funfly is HEAVIER but has more powerful, BUT now which one would you pick? The thing here is whilst the 46 one is more powered, the 36 has better agility, can turn tighter and fly slower

Power most of time comes at the cost of wingloading and weight, though sometimes. It is better to have a heavier engine upfront to cope with a tail heavy plane than have a light engine and load of lead. One thing you don't want is "dead weight"