confused and don't know what to do

I agree that you have a challenging room. Bookcases full of books, CD's, records, and 'things' will soften that a lot. Persian carpets are cheap these days, and some are very beautiful. That too can soften the sound, and they can look elegant on a wall. WAF is good.

Speaking of WAF, my system has been improved by her as much as by me. My lady has better ears, as women tend to. Listen to yours.

I agree that you should try as much of the system at home before you buy - at least the speakers. You may find that speakers which sound wonderful - clear, brilliant, exciting -  in the dealer's specially treated room, sound unlistenably shrill in your highly reflective environment. That would be a lot of disappointment.

Better to err on the side of mellow sounding components that you can listen to for hours, without fatigue. It's going to be hard to nail this first time out, so it would be better to have something which is pleasant, if not perfect.

Just my $.02. Good luck!

And don’t spend big bucks on cables first time out. Get the cheapest you can find, then swap them out for better ones, one at a time, until you find something that is worth the cost. I use quality microphone cable (Canare StarQuad) with quality connectors (ETI, KLEI, Switchcraft), nothing too exotic, for interconnect, and continue to find better uses of money than cables - better electronics, better crossover components, better records. Maybe when I hit seven figures ...

I'm not an engineer who can provide reasons why one type of amplifier is better than another etc., but I can provide my experience with wanting a system that can both play music and be really good at home theater. I realize that brands like Marantz, Denon, and Yamaha are scorned by the music listening only crowd, but to me, there's no better or cheaper way to set up home theater than with one of their AV Receivers and then deal with the music listening part of the system with a separate amp. Just be sure the AV Receiver has enough power to drive the center and surround speakers. As far as the AV Receiver manufacturers go, be aware that after a merger with Denon, both Marantz and Denon were subsequently purchased by Sound United. I'm always concerned after mergers and acquisitions like these that cheaper components will be used by the new parent company to increase profits. If I were going to buy an AV Receiver, I'd look no further than Yamaha. They have not gone through mergers, they use high quality components, and have the best reliability ratings of any AV Receiver manufacturer. I'd go for at least a 7 channel amp like this one with a lot of bells and whistles, which would cost a great deal more to get in separates:  https://usa.yamaha.com/products/audio_visual/av_receivers_amps/rx-a1080_u/index.html 
For just music listening, I own a pair of Magnepan 20.1s and I drive them with a separate 300 watt at 4 ohms Emotiva two channel amp. I also use the Maggies as the front speakers in the home theater setup. To my ears, the system works great for both music listening and home theater.

Many opinions found here, can be rather daunting.

Here's my two cents.  Figure (really think about it) out which "system" you are going to use.  If you are a major music fan then build a stereo.
If you watch movies constantly then build a HT.

I've had both in one room.  Totally separate systems.   

Try to remember that music appreciation is a "warm" endeavor, whereas
video is a "cool" endeavor.  

Personally I would build the stereo first, simply because that's where your dollars are going to make a difference.  Home theaters are a lot of fun but not as much as fine music system.  Good Luck.    

The B&Ws are bright - I literally can't listen to them! 
Paradigm has made affordable audiophile class speakers for decades.
They also have a complete line of really good in-ceiling, in-wall and subwoofers. I would check out the Prestige series.
They also make one of the few really good AV receivers - the Anthem MRX 520, 720, 1120. I recently listened to an MRX 720 driving a Wilson Audio left and right, with Paradigm center, surrounds, and subwoofer. With an Ayre DAC feeding it the sound was stunning!