Is there already power in place? Extremely rare for power to be in place without any wiring in place. If you said it is there already and I missed it, then I apologize.
In my opinion - cut the drywall, run your wires, repaint.
This is your home, not a quilt. Don't try to find a work around. Don't just do it to get it done, but get it done in a fashion which will give you the absolute best results, with the highest reliability for years and years to come. It may involve some extra work to do it that way, but it certainly will give you the best results and once it is done, you won't need to do it again.
You should run, at a minimum:
ONE HDMI wire (get a receiver which coverts everything to HDMI!)
At least three pieces of CAT-5/6 cabling (network, control, future)
Speaker cables as necessary
Go straight up the wall into the celing cavity, take it over to the soffit, then down the back wall to the equipment location. Should take three holes, maybe four to accomplish this and should take about two hours.
The drywall repair and painting (new home right? paint is an easy match!) work will take far longer than running the wires, but the end result will be extremely clean and good looking.
