what realm are you playing in? could help when looking for stuff "hanging" in mules

as for builds, i really dont think they vario THAT much from normal builds.. meaning that if u have good normal build it should work in elite too.
as for your summoner i can give some information:
demon pet : Warper. overall most used minion, does HUGE splash dmg
elementals: try getting 5-6 force eles and 3-4 other elementals rest points into master of the elements and spectral strike
so:
10/10 warper
5/10 force ele
4/10 fire ele
4/10 toxic ele
4/10 storm ele
7/7 spectral strike
5/5 Master of the elements
1/10 elemental nova
3/6 bloodlink (the one that u use to heal your minion not 100% sure if it was bloodlink)
rest into summoning circle
somewhat like that should be "ok" build for summoner
ofc there are others but builds that use warper is the most used and wanted.