John, your post was very thoughtful.
I have been rummaging my brain for information that could help you. Mari's last post was extraordinarily helpful. I think you should bite the bullet and go the atelier route if you can. I am primarily self-taught except for the two miserable years I spent at The Boston Museum School. I would have killed for the ateliers they have today.
Never be intimidated by age or circumstance. After toiling in the fields of commercial art for many years I decided to teach myself portraiture starting in my 40's.
Point of view is the single most valuable painting tool. Skillfull paintings without content can be just greeting cards. Read Chogyam Trungpa's "Dharma Art" (Shambala). He is the reason I still paint. I am not proseletizing here. Trungpa gives the most consise defintions of the process of visual perception I have ever read. His discussions on the purpose, power and necessity of aesthetics are profound. He discusses the importance of craftmanship and reverence for ones painting tools.
Nuts and Bolts: or not putting the cart before the horse. (My major failing.)
A.Drawing. Draw as much as you can from life. Learn classical proportions. If you don't know them I will try to describe them or attempt a scan. This is the backbone of painting. I'm not totally sure about anatomy. To quote Ingres "C'est science affreuse." (any French help here?)
B.Learn your mediums. Investigate brushes,paint etc.. Peg Baumgartner says never use cheap quality anything even when you are learning. Keep on hand "The Artist's Handbook of Materials and Techniques " by Ralph Mayer.
http://www.portraitartist.com/bookstore/materials.htm
C.Work in natural daylight even if you have to put up a tent. White only. There are color balanced lights you can use to augment daylight.
Some final notes. I will be giving a more consise breakdown of my methods of photography in the photo thread. However here are a few tips to get you going. Do not shoot in open daylight with the subject facing the sun. Pray for overcast days. The subtle illumination is beautiful,the skin tones saturated as the clouds act as a filter. Take advantage of open shade, i.e., under trees. When shooting outdoors if you are near or under trees use an skylight IB filter to get rid of the greens. I only use two Nikon lenses. They are sharp as tacks and were recommended to me by my friend Marilyn Silverstone. She was an accomplished photojournalist for Magnum and could make art out of any situation.They are the NIKKOR 85 mm 1:2 and the Micro-Nikor 55mm 1:28. They are sharp and the shots can be made into beautiful blowups. She used no automatic anything.