Tricky Room Geometry Question

Hi,

I am rethinking my system after realizing that I was not going to be moving as planned. My system is in my main room in a smallish house: it is 13 by 15 feet, backed by a stairway to the second floor, and otherwise open to a roughly 10 by 10 foot room. The ceiling is slope, 10 feet in some places, 20 in others. I currently have Thiel 2.4's, but in practice have not been able to position them as recommended (a few feet off of each wall, and 8-9 feet from each other and listener), the room just doesn't allow it. I had bought the Thiel's in anticipation of a move after falling in love with them at the store...but if I am going to be here a few more years at least maybe it is time to rethink. I have a VPI turntable and a Manley Stingray amp. I had planned to replace the amp with something more friendly to the Thiels, but given the room geometry think the opposite approach may be better. I mostly listen to 60's-70's pop music and classical. My budget is probably around $5k. What could fill this weird space but sound good when close to the listener? Any opinions are much appreciated. Thank you.