I don't see why two human companions is unreasonable, just because some people abuse the system. I vote against.
Because you can send another two and then another two and another... you don't have to control the mercs to make them work. Shoot at enemy once, relog/forget/get proxy for another pack. Pve players can have their dogleaders, slavers can have their slaves. But keep them out of pvp. If mercs are used and teams are even, the side that doesn't use them is strongly encouraged to do so or suffer defeat. Don't force us in arms race please.
I'm one who thinks PVP should be more of a sandbox affair with teams set up in a skirmish screen; the fact is there should be more regulation and oversight without messing up the game for everyone else playing. ... when the PVP timer starts
But I think mercs should have removed auto-attack order, it's the lamest part of mercs.
Personally I like that towns are open and you can never be sure what will happen.If someone wants to play regulated matches there is Hinkley.