Don't want to make it too hard on you - and only bring some of this up because you're the one that mentioned audiophiles.
What are you primarily going to be listening to: music (and what genre) or movies?
With music, and primarily stereo sources, a good receiver and a pair of nice speakers is typically enough (maybe a sub here).
If movies are your prime interest, then you'll want at least a 5.1 setup and the sub is a very important part of the picture. Note: you will have to replace the piece of junk sub that comes with any "home theater" combo package in a relatively short period of time. Well, maybe not - I have friends that are tickled pink with the $4-500 receiver/5.1 speaker package they bought.
What volume do you use? As an old ex-musician, I still believe that music is meant to be "listened to", at the volume at which it was played.
If you're actually going to get into the testing mode to find speakers, this is the volume at which you need to conduct your listening tests. At lower volumes (what I call just having background noise for while you're doing things other than listening - and this
is what most people do) you'll find much less "difference" between them and their importance can very quickly become almost insignificant.
I'll also reiterate - budget is the first consideration here. Because most of us just simply cannot afford what we really want when it comes to sound reproduction. My own guess - you could very well be happy with that Denon you posted for several years, although if you can listen to both of them, you might compare with the Onkyo at the same price point.
imho: With a budget at $700 - $1,000: go for the receiver you want - verify it has all the inputs you'll need, especially if you may want to use it for audio/video switching - then the best speakers with what you have left - planning to replace them in a couple of years. With a $1.5-2k budget, look at speakers first and then receivers. And for the true audiophiles, the price can go much higher (I paid $1,200 just for the needle on my turntable back in the early 70s - another reason not even the wife was allowed to touch the vinyl).