When moving an e-mail it would be nice if the hot-keys for OK, Cancel, and New Folder required pressing ALT or CTRL, like ALT-O, ALT-C, ALT-N so you can search for folders that start with the letters O, C, and N.
Currently, if you type any letter other then O, C, or N it will jump down the list to folder names starting with that letter. But if you press O, C, or N it will activate the buttons. This is a bit of an inconsistent behavior and also makes jumping to folders with those letters impossible - making the whole feature a bit less handy.
It would also be nice if you could type several letters like ‘Acc’ to jump to a folder named ‘Accounting’. This is available in some other e-mail clients and one of my favorite abilities 
When you’re sorting a lot of e-mail it sure makes it nice.