Best Evolving System Link + core combinations for training?

It is if you're taking like a 100 bishop/phantom giving you HS.

You have to remember that the mobs will always depend on your partys avg lvl, if you were to bring a lvl 100 phantom with you while you're lvl 140, you will get decreased exp, because the mobs will also go down in levels. Obviously if the person is higher lvl than you, you will benefit from it but he wont.

I'd say either you bring a hs mule inside for increased exp or you dont bring anyone else inside at all, especially in gms, go LHC/Stronghold if you want party play.

Hs mule stays in link 1 while you grind in link 3, go to link 1 for hs everytime you need.