Very much so, if you don't wanna pay for a respec token. I've had characters using it the whole year, even when its stats became far from the best. And it's also fun to mess around with transformations that don't use the humanoid skeleton, or to avoid the swimming movement type in specific instances.
Totally. I don't use mine much, but there are times where being a speedy boi is better than flying and it's better than carrying around a pack of bolt sport drinks.
Ring granting Super speed is already enough to buy it. Aside from that because of the health and dominance stats speed force ring has, it is better than 370 ring for buff trolls and healers. You can get it just for utility if you are solely playing as dps or tank.
Easier/faster/better to get to the symbols during the curse phase. Specially if trying to get the 4 seconds feat.
This and trying to click Zoom at each corner of the room is complicated as heck whilst dodging all of the other mechanics simultaneously. The time they give you to click him is insanely short