I feel for you. I've had some chemical burns from over-ambitious use of anti-aging products, particularly acids, and they can be difficult to heal. The longer I use Retin-A, though, the less I find myself needing to use acids at all...which I prefer. I use acids only occasionally in the summer now, and not at all in the winter.
If I'm understanding your post above, you're mostly concerned about dark spots?
For hyperpigmentation, there are a couple of things you can try, that aren't necessarily harsh. Vitamin C serum can lighten slightly, and it also gives a nice glow to the skin. PSF has an effective Vit C product that is mild. It's expensive though ($45 for a bottle that will last about a month), so I make my own with L-ascorbic acid, distilled water and hyaluronic acid. There's a thread about it over on the makeup board:
RCW - Homemade Vit C serum?
DianaYvonne.com carries a comparable Vit C as well. They also carry a natural lightening product, called Wildberry & Kojic Acid Serum, which does help with lightening also, and it's not going to tear up the skin.
Both Vit C and Wildberry/Kojic will help age spots only just so much. For real help, you'd need to use Tri-Luma, an Rx product which contains Retin-A, Hydroquinone 4%, and a topical steroid. That will really knock out the dark spots. It can only be used continuously for about 8 weeks though. I used it for that 8 week period, and my dark spots along the jawline and upper lip were gone, and now I use it once weekly for maintenance, and along with Vit C and regular use of Retin-A (and careful use of sun protection), I am able to keep my hyperpigmentation under control.
I purchase Tri-Luma from Mexico through mdmexskincare.com for $55 (plus $10 shipping), for a 15gm tube. That's where I buy my Retin-A from also.