phpMyAdmin takes a long time because it's getting a lot of information to display such as the different index commands and all. You'll probably see the header in the right page show up first, then the table much later.
Having 360 columns doesn't mean the table is unweildy. However I can't imagine a real-life database table that, normalized properly, would need 360 fields. I'll bet money it could be improved in some way.
Try studying up on the subject, try using comma delimted sets in text fields and pulling the logic out on the script side. It's easier for mysql to dump some data and let the script work with text, usually lightning fast.
Sam Fullman
