I think Bernth and Ben Eller make good instructional videos although this is the thing with practice right? It never stops and no matter how many times you do it you still have to go back to it haha.
As for jazz chords, i will say this, they create sounds that could be very useful in any genre of music but with more heavier tones they really do get brittle once you tack on gain and other things. Still, they are good for finger exercising and if you dont use them a lot they can be quite a challenge on day 1. I'd say the best exercise and as stupid as it may sound is neck traversal with variations. over the years ive seen exercises that focus practice on picking, speed, etc but neck traversal is very crucial to me as it teaches the person how to utilize the neck to play in octaves, etc. Try this exercise if you havent already.
He's got the charisma of cardboard but hes not wrong in what he teaches lol.