Speed-hacks like shorthand and stenographers' machines are for copying exactly what was said, not consuming and understanding it. I would be very surprised if there were not very old studies moldering in a paper journal somewhere investigating the information retention of secretaries / stenographers compared to "naive" note-takers.
I migrated to fountain pens and haven't looked back. Partially, it's because I enjoy the experience itself as much as writing, but partially it's because they've forced me to become even more deliberate.
I'd highly recommend it!
The learning curve is very gentle, you could learn it in a day. Honestly the hardest part is getting used to reading it fluently.
You can also look into various systems of abbreviations developed for telegraph (Evans basic English code), or you could look into using Yublin, which is basically taking all 2-letter combinations and assigning the most common 676 English words to them. Personally I like the idea of Yublin, with the addition of suffixes to modify common words so the word "add" might be "ad" in Yublin, but to make it "addition" you might turn it into "adn" and to further modify it to "additionally" you could write "adnly". This way you get more words out of your limited number of bigrams instead of polluting it with a word plus all it's commonly used variations. Write that shit in Orthic and you'll be flying.
Food for thought.
Yes! Nearly all my notes are mind-map-ish. I’m a visual thinker/planner with ADHD and mind-map style “spatial notes” are the only ones that make sense to me when writing and reviewing later. I’ve tried a few methods of moving this process to digital over the years but nothing sticks like pen & paper.
2. Obtain paper and ink that works well with the pen.
3. Practice cursive handwriting.
Possibly get a 2x improvement in speed.