Concerning the army value modifier- no, you should not decrease the advantage of coming into a conflict with a larger military force than the enemy. Firstly, it is unjust. Unless you want to develop a myriad of realistic features like terrain, training, equipment, supply lines that must be maintained, and great generals/leaders that could affect the war's outcome, you must allow the nation with a larger army to have a much greater chance of victory. In terms of how this plays out in the game, keeping tabs on which alliances are milling up and being politically aware so you don't get caught off guard is a vital part of gameplay that should not be detracted from.
Concerning 2. Nerfing superiorities- I like one aspect of this. In my experience every bitz begins with airstrikes. simply because halving an opponent's tank value is devastating and the planes can't be rebuilt at the pace they're destroyed. changing the amount that air superiority decreases tank value- so that it is not decreased as much as half- would be a beneficial change. But please don't institute two phase superiority. I know it's already on the test server... it has no significant benefits in my opinion, adding it just to make things more complicated is not doing us a favor.
Modification: only for larger nations
nyet.
(and no, I am not a "larger nation", most of my wars are updeclares.)