Honestly when I look at PoC mission tab, I pretty much mentally filter out the top line. I already know what it is, and I dong care about the stage number.
But i always glance over what Lv. of enemies will be spawning and how much oil it requires to run the map. Thus when I speak about PoC mission I always use the Lv. system, because its more relevant, giving you the idea of what strength the opposition will be and how much it will cost. I doubt anynone remember these when they hear the number of the stage for example. Thats just me though.

Now on a different note. I underestimated my tanks. With the hard grind and addition of few new 5* tanks to my unit, that happened in the last month, I am actually able to get up to Lv.50 reliably, and can push one or two more maps If I really want to (though it starts to become to much of an RnG at that point as most of my tanks are below L30. still after swapping them in for the older one), so the stat difference quickly adds up.
What I meant to say is, that with this in mind I am able to collect the usual 2-10% rewards, so thats at least something going on for me.