I've been boxing melee characters for about 5 months, using 1 warrior + 2 holy paladins. There are two ways to solve the 'follow' problem, either have your main back up a little, or bind the forward key to your key broadcasting script (for your alts use a different key than your main's forward key). I prefer the latter method because if you use the former method, your alts might run past your main when you back up too much and not be able to attack with direction issues. I have way more control with the forward key bound to the key broadcasting script (I use AHK). Even if your alts are facing the wrong way, you just make them follow you again and then press forward key once or twice to get them attack again. For every fight what I do is have the warrior charge, and as my alts run to my warrior I do the usual thing with seals, judgement etc. Then as they come close to the warrior I press forward once or twice then they will be in melee range.

If your target moves just move your main with it and have your alts attack from the sides. I find that my alts are more likely to attack from the sides as I move my main. All it takes is practice then it just becomes natural. Keep in mind though you will be pressing keys a lot and jumping and turning with your characters.