I'd prefer two things...

A/ Lupon behave somewhat like a "pet" that is follow you and commandable "stay/target". In abyseea not to much of a problem leading a bunch of mobs in field effect..but playing solo(Im lvl 16)... it 's a pain in the butt to run mobs over to your circle. yes, I know "full circle" and recast...but it's a long casting and im lazy. The mobs in regular field are much more dispersed.

B/ Lupon gain effect over time...for example, much like avatars "aura" effects. I know summoners are gonna hate that one(btw, Im a summoner also).