Ive noticed some empty cells, and various other HTML coding that really isnt necessary, if you removed it all im sure itd help with page load time for people. no matter how small of the change it. Perhaps you should have someone chk and remove useless lines of code, or replace...
--- Empty Cells ---
Top left, on the index, left of the "forum" word
Top Left, on a forum w/ posts, two empty cells there next to "Topic/......"