Yes, Solve the room situation first. If you don't do this, then nothing will sound good.
Our floorstanders can help you solve the open port space in your room. And in those corners, you will probably want to mount some Framed Responses (they can be corner mounted and we will supply the mounting bracket if requested) that will help balance things out for you.
Currently, we have a list of speaker placement tips that we may edit and put on our website. But for now, try moving your speakers in so that they are about 8.5-9.0 feet apart. There are certain golden ratios that tend to work depending on room and system.
What you may want to do is fax or email a diagram and/or pictures of your room: blaurent@eighthnerve.com / Consulting faxline 212-937-3512.
Startlet. Do you live in Singapore?
Cheers and Sincere Thanks,
Bill Laurent