Hi,
Thanks for this (love your room design and decor, by the way!)
The two Yamaha receivers are particularly good, they work well and are usually very reasonably priced. It is worth noting that when building a surround system, a law of "diminishing returns" applies, ie (percentages are approximate):-
50% of the sound goes to the centre speaker
25% of the sound goes to the front speakers
10% of the sound goes to the subwoofer
10% of the sound goes to the side surround speakers
5% of the sound goes to the rear surround speakers
Hence, getting the centre, front and subwoofer speakers exactly right is often more worthwhile than adding lots of channels.
Speaker positioning isn't critical, but getting a "left to right balance" is very helpful to the listening experience. Looking at your photo, I would suggest using the S8 satellite speakers and subwoofer as your front and bass speakers, but ignoring the A9 and Shape speakers when playing movies (these can be assigned to extra "Zones" on the receiver, to allow you to add them in for music and parties, etc).
The two rear Beovox 2-2 speakers can then be linked into the passive outputs of the receiver (please connect to the "Surround" outputs before using the "Rear Surround" outputs unless you are using all the channels on the receiver).
The best thing to consider now (instead of linking the Shape and A9) is a really good centre channel speaker to sit below the TV - this will carry all the dialogue and centrally-placed sounds, so it is the most important part of the speaker system. B&O's Beolab 7 speakers are perfect for this role.
Please let me know your thoughts and I can help you to get everything working!
Kind regards, Steve.