Every effect of the hospitaler paladin's Aura of Healing specifies that it affects allies within range. Almost every effect also specifies that it applies to the paladin themselves. The one that doesn't is the limitation on healing and additional saving throws. I'm inclined to think this means one of two things.
First, the omission was intentional, and the aura's limitation only applies to the paladin's allies, not to themselves. Second, the omission was accidental and the aura has the same limitations for the paladin.
I've been looking, but I can't find any errata or FAQ or anything that answers this question.
Core FAQ: You are your own ally (unless it would make no sense).
Thank you. Based on the wording used, however, I'm still inclined to think that the limitation may not apply.
The two primary effects of the Aura specifically call out that they apply to the paladin, while the last bit about how they're limited does not. If the intent was to default to the intent of the referenced "your allies" wording, the parenthetical note would be completely redundant. This, of course, would fall under the "unless otherwise stated" bit of the FAQ.
The release dates for the FAQ entry and the book (APG) are quite close, which doesn't help matters much.