So the horn of command is currently one of the only ways to control units. however there is one major problem with them. The clutter. Normally people have two horns per squad or whatever and I usually go into major battles with at least three squads. Now with three squads thats 6 horns plus 3 swords of command plus a primary weapon, polearm, ranged weapon, healing supplies, food... and soon you have no space in your hotbar.
Thats the problem. Now for the solution. I propose to switch out the two types of horns for one. Instead of choosing summon or halt/go whenever you use the horn (which will no longer have the charge up due to taking too much time) it will pull up a gui allowing you to choose wether to summon or halt/go. this will limit the amount of horns in the inventory and will open the way for new commands such as retreat, disperse, etc.