Troy-
What you garnered from your reading is about the way it is. There are countless powders available with overlapping capabilities. However, Stimpy gave you the goods there per your question. Anything beyond his recommendations per your question becomes pure individual opinion and/or preference. Period. Follow his advice on powder selection.
Your reloading manuals will tell you how much to use for each application.
(Opinion) Your weapons will tell you, in time, if they like it or not. Listen to your guns. Later on, with experience, you can expand to other powders of interest. Don't get all paranoid and hyper about stuff. It is pure science, but not exactly rocket science. You are just getting started, so spend a bit of time on the basics, brass prepping and stuff, and having fun with your handloads. Keep notes (a notebook helps here) of your load, weapon, shooting conditions, target results, etc. I even make an entry if I need to try something again or move on. Sometimes you find a loose screw in your weapon or sights has made you think you had a bad load when essentially you just had a bad day. As your manuals state, start with the starting loads and analyze the results. Make it a fun thing. Take your time. Try to stay away from 'hot-rodding' your loads. Nothing you will hunt will need it. We, as a handloading fraternity, tend to use far more 'power' than we need to get the job done humanely. Whether you are hunting or punching paper, "the most you can get out of your weapon" will rarely be the "best load for the job". Placing the bullet where it needs to go is the name of the game. Your carefully prepared handloads (not referred to by me as reloads) will help you facilitate that. The rest is practice, practice, practice.
Reloads - cartridges that have had the primer, powder, and bullet replaced.
Handloads - cartridges that have had the primer pockets uniformed, flash holes uniformed, primer replaced, brass trimmed, powder carefully selected and measured for the weapon and application, bullet carefully selected for the weapon and application and seated appropriately - one at a time. Or something like that.
Guess I see reloading as 'basic handloading' and handloading as 'advanced reloading'.
I and most of my brethren are Handloaders, not Reloaders.
(End Opinion)
Welcome to the Fraternity!
Regards,
Sweetwater