What does the 1123 have you want?
The app control?
Otherwise...there is little difference (not heard anyone say advanced MCACC is any better than basic).
Setup should be(not familiar with Pioneer)...
Front as large.
Wherever a Quintet is...is small.
I would toy with LFE + Main to see which you prefer.
Subwoofer(didn't look at how the connections are labelled) should be set crossover all the way up...as the AVR is handling the crossover.
Not heard that speaker...but in general...the bigger the speaker...the more full sound you end up with.
I'm the last to ask about "specific speakers"...
My 4 theatres are BIC V, DCM TF, Infinity Crescendo and a mishmash of 90s era Polk.
My gf has Wharfedale w60e in her listening room(where her upright bass resides). I have Dahlquist DQ10 sitting in the basement "rec area"
Yes the 1123 has better app controls, a little more powerful sound, corrections with some zone two issues, a couple of other things, it is not a lot different. I will only purchase it if I can sell both receivers I have now and get an equivillient amount of money. Unless someone can recommend me on another receiver to look at. Most likely though I will stay with the 1023.