I'll add an option for a toolbar button for the Rules Manager. You can also adjust the font of the Rules Manager window(s) from Rules Manager Options.
By sort them in the main box, you mean in the RM window? They can be sorted from here... The only thing is I may not have enabled the buttons on the version you have as it is a facility I have been testing. It is now working ok, but not sure it was enabled for the upload - also, I will be adding more sorting options. If it is, you'll see an up and down button as shown in the attached screenshot. If you can't see them I'll get an updated version up soon.
Filter... is useful for restricting the list of rules shown. You can restrict on either email address or folder (this is crucial really when you have lots of rules!). The Find... simply searches through the displayed list of rules for the next one containing the criteria you specify.