Like I said, beauty is in the eye of the beholder.
Speakers don't often "fry". You can feed them excessive power and damage them, but judicious use of the volume control will usually alleviate that concern (if it sounds bad turn it down). Not sure what you mean about right power specs. Keep in mind an amp spec isn't a maximum necessarily, most often it is specified for a maximum without exceeding a specified amount of distortion....but they can exceed that. With the receiver you have it is doubtful you have anything to worry about. What are the speakers you are planning to use?
The speaker wiring would be from receiver speaker terminals to both the sub and the speakers simultaneously (the sub will take the stereo inputs and sum it to mono). Some subs have an extra set of output terminals to the speakers for some flexibility like this pic I plucked off the 'net:
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