As an observation, that is quite a restrictive DMR rule at that particular site. Only 1.48j/400FPS AND a 30m MED is fairly punitive, and I'm not sure the extra few meters range that could be achieved with the additional circa .3J would in any way outweigh the disadvantage of a 30m MED.
As a comparison, I'm used to playing at a site whose DMR rules are 1.88J (equivalent of 450fps on a 0.2g BB), and has a MED of 25m. The additional power allowable gives you a more meaningful edge over the typical AEG, and the slightly lower MED gives you less occasions when you need to switch to a sidearm, and more of a fighting chance to be within the useful range of your side arm when you do have to switch.
Honestly, with the DMR rules at your site as they are, it would seem better to focus on squeezing all possible performance out of the gun whilst remaining below the standard 1.13J limit in my view.
edit: to add, i would expect that the measures which you have listed would do a very good job of extracting maximum performance out of the rig, at whatever power level you decide upon, but i will defer to the opinions of others who have better knowledge of this particular platform.
