Hi,
A website I worked on, was not super fast to begin with and now they added a lot of videos recently (linked to Vimeo).
I have SG Optimizer in place and wondering if there are any other measures I can take to increase the speed.
Would WP Rocket be a solution here, in addition to SG Optimizer?
Sorry, just seeing now 
You could check with WP Rocket and ask if it helps with the video. But I’m wondering if there are any other measures you could take like removing plugins etc.
Np, I think all normal avenues were explored at this point 
WP Rocket or similar would be the simplest thing to try.
Next up would be a better/more expensive server…