X-minute effects need to die a fast, horrible death. We have enough fudging of effect durations as it is. Prison is workable since you can ignore all other timed effects for the most part. But you can be Slept, Waylaid, Unconscious, Nausea'd, Drained, Diseased, Paralyzed, and more all at the same time, and have to keep track of each time limit separately. Why add to that pain?
I suspect it is more likely that players will conveniently fudge the ten-minute duration to be even longer while simultaneously continuing to play their detrimentals as much shorter. I'd rather see the duration as "per combat" (which tends to be pretty easily defined), or "per logistical period" (which is fairly rigidly defined).
Removing spellcrafting from the Damage, Elemental and Earth/Chaos Aura scrolls only helps the people that don't want to rely on Celestial formalists (for one, those are better defined, duration-wise and target-wise). Formalists like using their skill. It justifies the build they spent. Elemental Aura and Damage Aura are mainstays of Celestial casting. Removing that from their exclusive options makes them even less necessary.