Honestly, no, there are not.
There are a number of magical locations one can visit for permanent or at least long-lasting benefits, and various groups you can join that give you bonuses for affiliation, but these things
do not provide these kinds of bonuses,
tend to cost money someone with Vow of Poverty cannot have, or else “count as” wealth which interacts with Vow of Poverty in strange ways.
The last might be compatible with the Vow, arguably. You can read the rules for them here and make your own judgment about how they interact with poverty, but they are literally called “Magical Locations as Treasure” so if we are pretending that the Vow of Poverty is actually balanced and its limitations need to be taken seriously, it would seem these “should” not count.
The other thing someone with the Vow might arguably do is pay church tithes, since these are required for a number of affiliation bonuses. But that would involve using money for your own benefit, so they also seem like they “should” break the vow.
But it doesn’t matter because none of them provide the bonuses you’re looking for anyway. This useful handbook claims to list all of the magical locations and affiliations out there; none of them (that I can see; feel free to check if I missed one) improves any of the parameters you’re interested in improving. It does reference some useful tools that appear to have gotten lost in some Wizards and/or Brilliant Gameologist board migration (such is the case with much 3.5 material, sadly), so there may be more out there, but I do not think any will help you.
Which brings us to the realm of houserule. You could easily rule that church tithes and magical locations counting as treasure don’t break the Vow, and then invent such things tailored to improving this player’s character. You could also allow the character access to the Touchstone (Sandstorm) or Planar Touchstone (Planar Handbook) feats without their costly, well, touchstones, and then get access to the much broader collection of touchstone sites—this thread has some useful tips there, and there are even some bonuses to AC in there (but none of the other parameters you’re interested in).
But at that point, we’re already messing with the fundamental premise of the Vow of Poverty: that it can completely replace wealth for a D&D 3.5 character. This is, of course, simply and utterly untrue, and while dragonfire adept is one of the better classes for the Vow, the simple fact is that the Vow, in fact all of the Vows, are terribly designed and really should never have been published. (I would also argue that a character with the Vows of Peace and Non-Violence is not appropriate to a D&D 3.5 campaign, but that’s getting beyond the subject.)
It’s worth noting, at this point, that even if such a character were willing to invest them, feats and class levels tend not to offer these kinds of improvements. They do occasionally, but usually in small numbers, and overpriced. Magic items are 3.5’s answer to the question of how to improve these numbers. Without items, you are very limited in your ability to improve them, because everything else is priced with the idea that you are adding them on top of items you already have, hence the small numbers and tendency to be overpriced.
Thus, my strong recommendation for running a character who does not use material wealth is to give them “items” anyway. I strongly recommend that you largely throw the feat out, and instead provide item-like bonuses in the form of blessings and the like to characters. Item guidelines suggest that an item should cost double if it does not use a usual item-slot; you could use that as a baseline for how to grant this character these item-like bonuses. Then this character can simply have a blessing of health +6, a favor of charisma +6, a +1 soulfire chain-shirt-like boon as “armor,” and so on. Wealth is too integral to the proper functioning of characters to try to throw it out and replace it with a one-size-fits-all approach, as Vow of Poverty attempts to do.