I just found out by using the Getlevel command on pc. I was curious which level my Summons might be. Turns out, my Dremor Lord is Level 46 with me beeing only Level 20!

My Storm Atronach is Level 30, no whonder they are lacking compared to Dremora Lords.

I though this would be an Interesting find, seems i was wrong^^

It's kind of disappointing if you ask me. Unless your in a particular summons level range, it's either OP or UP. I wish they would level with you so you could strategize (use fire atronachs against things weak to fire, ect...) instead of just picking your most powerful summon and never using the weaker ones again.