Maria:
My room is 21*13*7 and have had floorstanders with great success...set up on the short wall and speakers way into the room if they like to be such as Avalon. You may want to keep the floorstander rather slim, tight bass, may be a 2.5 way with woofers smaller than 8" but you can have full range for sure...Utopia Diva may be an option but at this price range, you have plenty of choice Avalon Ascendent II, Audio Physic you name it, Living Voice OBX, Merlin VSM top of the line, etc, etc. You may not need huge amplification, a bonus.