I agree totally. I am planning basically the same thing. One El-Mod pro set on about 3 different tanks, so far. Then I'll just make a SD card for each tank.
Servo elevation is the best way to go. Did it on my HL/Tam Pershing conversion and it works great.
I will be using servo elevation on the new Tamiya Pershing I just ordered from Karen at the AAF. Just need to get a few bits and pieces for that project. It has been awhile since I built a full Tamiya kit.