Speed
Back in the 60's, 70's, players were judged for money matches on a scale of 1 to 10. These speeds came into play when 2 players were negotiating a game, and possibly a spot.
Today, that scale is 1 to 15 with Efren being a 15. Most amateur handicapped 9 ball tournaments anymore are handicapped 2-12. Tony Fargo, for example, played here quite a few times in Shooter's Thanksgiving tournament as an 11.
I, on a personal basis, rate players to 1 or 2 decimal places. For example, I might rate 1 player a 8.2, and another player 8.9. If they were to play each other in a money match, I would bet on the 8.9. I am basically saying the 8.9 is 3/4's of a ball better than the 8.2.
First, you judge a player's form and stroke, next how good they can run out with a variety of shots, next how good they break, next how good they can bank (a lot of players don't pass this evaluation), how good they can kick (again, a lot of players don't pass this), how good they can jump, and how good they can masse, and how well they stand up to pressure. That's my basic evaluation of a player to judge their speed.
And I notice whether they have any form or stroke deficiencies when they are under pressure, like twisting their wrist, gripping the cue too tight, punching the cue ball instead of stroking it, gripping the cue with a full fist, etc.. Oh, bout forgot, you have to consider whether they are basically a money player or tournament player. If a money player, what level of money do they play for, or have played for. There's a difference between a $100 a set money player from a $500/$2,000 a set money player.
Anyway, that is how I do it, and have for a long long time.