Scott Lee has a speed drill where you practice lagging the cue ball certain distances. You may be able to find it with a search on this site.
Bob Jewett has some drills at sfbilliards.com (click on the link for miscellaneous files, then number 4 - progressive practice drills). These are really good because you move back and forward at different distances which sort of naturally builds speed control. (
http://sfbilliards.com/miscellaneous.htm).
Also, at Billiards University, Dr. Dave Alciatore has playability exams that work to build speed control. (
https://billiarduniversity.org/testing/exams/). Click on the links for the several sets of exams.
On adding the pause at the back of the stroke, I've done that and it has helped me just as Patrick Johnson said. However, I would think hard before changing your stroke at this stage. If you're making steady progress and have a repeatable stroke, I'd work with drills like those mentioned and save the stroke changes for later. Maybe get an instructor to help with stroke changes when you start to platuea. (Tor Lowry has some really good stuff too, btw, but the drills mentioned above are nicely focused for where it sounds like you are at as a player).
Hope that helps. Shoot well!