Melee is bad for multiboxers if it's not your main, it breaks follow and follow is pretty much everything for us. Same with channeled spells like arc missles.

Clicks I -think- can be done with Autohotkey and synergy or multibox or one of those other programs, but for the most part passing clicks is complicated if not impossible in most cases; it gives too much functionality that it borders on bottability lol; you'll just have to get used to alt-tabbing or run 1 on laptop/1 on desktop and connect 'em with octopus/synergy or if you're willing to pay $40(for a pre-setup, high-support that's usually worth it), keyclone, 1 license per comp