Keep in mind, though, the limiting factors of the learner.
First off, the learner's talents are limited by a wide variety of things.
She is limited by her level, because the effective spell level of her talents is based on that. That modifies saving throw DCs for anything vaguely offensive. It also means that most of her talents are easy to dispel by a caster of equal level, since they are going to be probably 2-3 levels lower than what she would be throwing if she were a wizard or sorcerer of equivalent level. In addition, any ability that is normally always active for a creature lasts for 1 round/level for the learner - and there is no way to extend that, with the removal of metamagic feats.
She is limited by her abilities. A learner suffers from MAD of three ability scores, modifying her saving throw DCs, her talent slots, and her talents known.
She is limited by how many talent slots she has in a day; at 10th, she will probably have 16-18 talent slots available. If the talent slot costs of SQ abilities are increased to two, that means she can use - at most! - 8-9 of them in one day. That's only 80-90 rounds of mostly defensive abilities. If she uses any other ability, those numbers are cut drastically. Sure, she can get DR 15/magic and bludgeoning for 10 rounds, but then she's reducing what else she can be doing. She is far more limited than a sorcerer in her available power.
She is limited in what she knows, period. Yes, using that as a balance argument is somewhat shaky ground. However, a learner can only know so many talents, and she will probably want a decent mix of abilities. How many DR abilities will a learner bother to learn? Will she take the DR 15/magic and bludgeoning, or the DR 10/good? They could choose to take both, but then that's one less offensive or other miscellaneous ability they could gain. And while they can swap out abilities, if they do, that ability is gone and must be relearned manually, which can take quite a bit of effort.
And any party with a cleric has access to a spell which enables them to overcome DR -/good. Align Weapon doesn't require you to choose what alignment you're going to use it for when you prepare it. And even then, it would be no more annoying than encountering an enemy for whom you do not posess an item of the appropriate type.
The learner has many possibilities at her disposal, yes. But her talents all have very short durations, they are all relatively low-level (and therefore easier to dispel at higher levels), and she has a very small power base and list of talents known.
Sure, Unearthly Grace is nice, but what about
this spell? At 11th level - a learner would probably be at her 4th or 5th level in learner, tops, at that point - a wizard or sorcerer has access to a very nice combat spell. And the wizard doesn't have to hop through a bunch of hoops to use it, either - and when the wizard first gets it, it will always last longer than the learner's Unearthly Grace, no matter what level.
