Recommendations please...

Good afternoon to you all!!

Just moved into my new home and I would appreciate some suggestions...gots me an 12 x 15 living room....vaulted ceiling...wide open from front of the house to the back...kitchen to living room...everything I have seems to be to off for the place...nothing seems to sound right...looking for new speakers...suggestions??

The equipment is set up on the 12 ft wall with bookshelf speakers placed 16" away from the wall and about 7 ft apart...I'm about 12ft back when listening. To the left of me are windows with full drapery...stretching the entire wall...the right is wide open into the dining room and kitchen. The vault runs front to back over everything...ceiling height in the living room starts at 8 ft and rises to 12 ft above the dining room then back to 8 ft in the kitchen.

The floor in the living room is hardwood...no area rug...there is a couch, loveseat, chair...no coffee table...numerous plants...large painting on the opposite wall from the speakers...no glass though...a few smaller paintings behind the speakers...canvas art...no glass.

I don't know if its the vaulted ceiling or it being wide open...thinking of something mellow, airy and sweet...budget around 500.00 new or used...anything fit the bill?? Equipment is Pioneer Elite's along with digital from my computer.

Thanks kindly!!!