Is there such a thing as too much power?

This thread is worth a read (you can get the gist from the first two posts). By following the instructions you can work out how much power you need. If you look at the poll results you can see that  >70%  indicated 25W or less with nearly 40% needing only 4W.
Power in itself is not a bad thing but assuming you are working to some kind of a budget then it would be best to find the highest quality amplifier that meets your needs within your budget. Power adds significantly to the production cost of a product (less so with class D) because some of the most expensive components within a power amp are the power supply and heatsinks the size of which are proportionately related to the rated output power.

If you're speccing an amplifier you need to go for the amount of power that you'll actually use plus a small amount of headroom. That doesn't sound very helpful but in order to optimise your system properly you need to understand the gain structure... if you've got a 1000W system and you never turn the volume higher than 30% then you're hearing more noise than you need to because every time you attenuate you move the noise floor closer to the signal level.

This is true regardless of the quality of the components you are connecting together. If you factor in the trade offs that need to be made when designing an amplifier then you'll work out extra power will either drive cost upwards or other qualities (such as sound quality) down.

If you follow the instructions in the thread I previously linked you can work out the amount of power you use and optimise your choices. I'm happy to explain more if anyone wants.