Armchair predictions are fine, and I'll make some, but there's nothing like an informal test shoot to clarify your workflow before you need to really get the money shots! For that most important discovery, shooting will be much better than reading.
20 to 30 feet away? What room can you shoot in that will give you that kind of space?
I'm guessing that a test shoot will show that the 50 and 24 on your full-frame will be most useful. Getting a head-to-toe to show stance in a typical room... well, it would be nice to catch it with a 35mm or longer lens so as to not introduce visible wide-angle distortion. As you get longer, you're going to run into other pool tables (pool hall), or walls (home), unless you have access to some sort of large dedicated space.
Arguably, your shortest full-frame lens should be 28 or 35mm in an instructional project that involves straight lines and the geometry of shots. But, depending on the space, you might have to go shorter
Apply your own crop factor calculations for the t3i.
But your headline was about lighting. Here too some test shooting will help clarify whether you have sufficient light. If you do need more light, the classic approach to a table with person or people around that needs a boost is to fly chinese lanterns, aka paper lanterns. They are so light that you can fly them off existing fixtures, or, a long crossbar between stands.
2 or 3 of these as low as possible over the middle of the table, with 200w bulbs will light the table and the player very nicely. You may need some other light for your off-the-table stance shots.
Here's a nice intro:
When you buy them, about 24" is the minimum size that's useful, and, you buy the cordset, bulb, and lantern separately. They're cheap! Don't set the house on fire...
From the upper left corner of the U.S.
Photos, Video & Pano r us.
College and workshop instructor in video and audio.
70D, Sigma 8mm, Tokina f2.8 11-16, Canon EF-S f2.8 17-55, Sigma f2.8 50-150 EX OS, Tamron 150-600VC. Gigapan Epic Pro, Nodal Ninja 5 & R10.