Speaker power ratings at a lot like auto speed ratings. Just because your car will go 300 Km/hr doesn't mean you can or should. Just because a speaker can absorb 400 watts with exploding in flames, doesn't mean you should try, or need the capability. Avoid audible distortion at all times. Turn it down.
More important is the sensitivity (dB/watt) as long as you don't force too much power into a speaker rated for less (remember those flames).
A 50 watt amp will happily and safely drive a speaker rated for 1000 watts, but just not as loud as it could get. However, overdriving the 50 watt amp (distortion) can cause some speaker parts to overheat and fail, commonly tweeters. Otherwise, there is no need to match any amp to any speaker beyond quality. Certainly, power ratings should not be considered when "matching". It is Quality, Quality, Quality.
Buy the speakers you enjoy listening to the most. Buy enough power to get them as loud as you want in your room, without exceeding the speakers' power rating by a large margin (say no more then 2x the speaker rating).