True, but mastery of the force isn't everything in fights (usually more influential than lightsabre skills, but still). Vader is in the same ball park but the fact remains he has no feats to place him as an equal to Galen.
Other than fighting Galen to a stalemate. Not saying he's just as powerful. Just powerful enough in the force to hold his own against Galen. That was also without his legs, which made him weaker in the force as a consequence. In this match the OP specified that Vader has them.
Again, I find that passage problematic; if every single energy weapon fires a lightspeed blast, then how on earth do so many dodge their blasts? Not even force users, but Han, Leia and several others. But even if we were to only use force-users, how is it that they could deflect something that was lightspeed and yet get tagged by so many things that are obviously slower? The fact is, we can't take that as fact because it is contradicted by so many things in the movies, the books and even the comics.
Well, not all weapons are light-speed in Star Wars. The hand held blasters are obviously not but that quote was in reference to turbo-lasers (which AT-AT Walkers are equipped with) and other weapons like them. As for instances for when they're tagged by something slower could you elaborate?
Which characters and how? Be aware that inconsistencies do happen in Star Wars just like any other piece of fiction.
As for Vader and telepathy, I find you are still missing the point; I know that Vader can do it, but IT WOULD NOT BE IN CHARACTER FOR HIM TO DO SO. Sure, if he's getting his ass handed to him he might use it, but in most cases he won't use it. Yes I remember his mind reading in episode 6; that was when Luke was hiding, making a frontal attack impossible. I didn't see him trying to mind-hack Luke when he was out in the open.
So, it's a matter of if he would use it? Well, I think he would since he's outnumbered and there's the whole fact that Galen Marek can twist around the minds of dozens of Storm Troopers (to attack each other), and Darth Vader was his teacher so I wouldn't be surprised if he pulls the same trick if he's cornered.
Plus, force precognition is likely to key Vader into the sort of situation he's in.