Isn't it a shame that there's no difference whatsoever outside of their duration? I'd like thrall atronachs to use master-level spells, or just different spells in general. The Flame Atronach never even gets an AOE fire spell akin to Fireball, not to mention that it's rather silly to have the same exact spell both at apprentice level and master level with the only difference being duration. With that petty difference in duration and a huge difference in casting cost, I may as well just cast the Flame Atronach whenever I need it, since by the time I'm able to cast the master spell, I've got Elemental Potency and Atromancy (not to mention significantly reduced casting cost).

Sheesh, at least make thralls stronger. The fact that the Flame Thrall is only as strong as the Flame Atronach significantly stunts its usefulness against stronger enemies, even if they're weak against fire.

Erm, I believe on the wiki it says that Flame thralls are stronger than regular flame atronachs. especially with elemental potency perk.

Just checked, they have double the health and higher fireball damage

According to which wiki? Because according to UESP, they're the exact same outside of duration.

http://elderscrolls.wikia.com/wiki/Flame_Thrall

No; thrall summons are significantly higher level than the "normal" creature -- for example, while an ordinary Flame Atronach is level 5, a thrall is level 30.

Also, out of experience, I'll say that I've found no difference between the Storm Atronach and Storm Thrall. Also, Elemental Potency is inconsequential, as both atronachs and thralls benefit from it; it doesn't make sense to say that thralls are any stronger because of that perk..

Ah well, if you're on PC and can simply look at them, I'll take your word for it. Maybe my mage should finally start using those thralls instead.

I keep around one thrall and keep the other Twin Souls slot available for a Dremora lord should he be needed. Also screw frost thralls they just get in the way and end up pissing me off.