If I’m staying at a Crescent Lake resort, is there a disadvantage to entering through the Int’l Gateway if I want to power walk to TT?
Probably a little disadvantage since you’ll have farther to walk. But i don’t think it’s worth going to the main entrance. The IG crowd is much smaller so you can arrive later and still be at the front of the pack.
Be aware that TT is down at rope drop quite a bit
TT is the more often recommended FP for Epcot because as @brian95 said, it is often down at RD. (And actually, other random points of the day.) So if it’s a must do, I’d definitely get FP for it.