Glad to "help", Trystan!
It'll be interesting to see what you get out of that 20" barrel. If you don't lose over 25 FPS per inch, I expect the new powders we've discussed can get you 2550' with a 250 grain, 2750' with a 225, probably 2850' with a 200. That's 100 FPS below what I get with PP2000MR (250s and 225s) and Varmint (200s) in my 23 inch barrel, and consistent with Speer's and Sierra's data (I am loading 1-2 grains less powder than either of those two sources used for max - I was happy with my results at the milder pressures). I have not played with CFE223 myself, but for all I know it might be better suited to the shorter barrel, or not, but worth a try also.
Are you going to have that Tikka rebored, or go with a new barrel? I used a 14" twist on mine and have been happy with that.
Best of luck and keep us informed.
Rex