This is because these 4 stats you see left to the milscore don't have something to do with it.

The only thing that is taken into account in the Milscore are ships that have, at least, 1 ATT. Basically, the game collects the sum of all your ATT, DEF, and an increment of the HP your military ships have, and adds this to the score each turn.

Note that the precise way under which this is done isn't clear knows, just that as the game progresses all your score-increments will "weigh" lower into the overall score. As well as there is a depreciation to the Milscore if you have weak Fighters, and/or many of them.

Strange feeling to adress a landsman in foreign language   

btw if click on the "Default" button when editing your MV characters your medals will show up.

btw how did you name your fleet?  

Generally there are two ways:

Playing ZYW's (these are very fast games)

or try to achieve ann insane Militaryscore by upgrading thousands of hulls to military vessels, and maybe put them under the MSBA.

There are numerous threads on these topics, just search around.

Judging from your MV profile, you played way too long into these games. From year 7 on there's not really much to gain anymore. Thus, you need to be fast, and this requires skill & methods.

Next, play on suicidal only. That difficulty has the greatest score-multiplier. In fact, some games on suicidal are even more easy than on obscene etc.

And, I see you play DL. That game is the hardest scorewise. Try DA, much more easy, and better conditions.

btw 30k score for a common warfight is a good score. And yes, big warships are best, but dont make the mistake of having one single tiny Fighter amongst them, this will take the Mil rating down. Actually, the 4 components that the overall score consists of are always visible within the game, it is the first 4 statistics in the "timeline" section, for Econ (income), Military, Population and Research output. The faster they rise and the higher they climb the better your score will be.

Try to max them and you'll see your score will rise.

Tip: Boost research very early and then change to an economical approach.

2 Tip: Play "very fast" technology speed only.

and have fun grinding them

btw a "veteran" I'm not. Started playing MV just some months ago.