That is a pretty good sized room. I would suggest a used pair of JM Lab Electra 926 or 936. They have killer soundstaging, don't need huge amounts of power, and do all the audiophile tricks while still sounding musical. They are killer bargains these days. If you opt for the smaller one (which I own), use the extra money to upgrade your cables and/or buy music. That's my suggestion.
Arthur
Arthur