You and I are very similiar. I do everything you mentioned in the first post, I learned the same way you did as well. I still love buy back day at college because there are some books they don't buy back that kids throw to the side and I take them home to read on break. I currently have a book on statistics and rhetoric next to me. Yes, these are for 'fun'. I love to learn.
What I did was learn in my public speaking class was twofold, to DUMB DOWN and KEEP DUMB. There is no other way to say it. People are not coming in with a lot of knowledge, nor do they want to leave overwhelmed. You are there to give them a basic intro.
I start out by assuming the person knows NOTHING about the topic. Then I write my presentation. I keep reminding myself that the people who hear this will NOT want to hear it (because this is generally true...most of us don't like sitting in a room listening to someone talk) so I want to keep the ideas short and to the point.
Now that you have written your outline, is there anything that the audience will already know? I simply cross it off my outline.
People like you and me want to learn, we need to remember others don't and they need breaks to take in what we are teaching them. Build in little breaks in your presentation. It can be a joke or just a little extra time on a power point slide before it will"move" on, but we all need to input the info we are learning. This is especially true when people need the information but are not likely (as you and I are) to learn more on it by choice after the presentation.
Break it up into a short intro-- perhaps a lame joke or memorable antidote, followed by what you will be presenting a middlle -- the three or four main points, and the end -- a recap of intro and middle. This style worked well for me in public speech class.
If you wish to share the subject or have any questions, let me know. I am more than willing to help you on this.
I am just glad to see I'm not the only one to learn this way.
BTW, for me it was a grasshopper I first took apart.
ETA because the curse meeter took out the word "power point" -- for once I agree with it!