Bamboo roller blinds are an inexpensive fix. They can be cut to fit and have a decorative look.

aac block will bear the load, so don't consider using for load bearing structure. if you use column and beam then you can go with aac. it doesn't give cracks. depends on the workmanship

Kramerlib, Is it just the window that gives away the privacy. How would sheer curtains or vinyls on the glass panes or reflective glasses work in your case.

Pooja's placement is what I was talking about, if you like the NiTi has placed it, shifting the wires is not as expensive an affair as you think it to be. you can pull them from the false ceiling. another thing you can do is use them as two separate pieces. have a C side table that goes under the sectional for a built in side table look for the right piece and use the left as a chaise. You could also shorten it. that will be cheaper but you'll need a skilled craftsman otherwise the structure can be compromised. since you're planning to reupholster, shortening it is also a viable option.