Generally I find the campaign enjoyable, but really hated the final mission though.. I hate to bring up the moba comparison, but that last mission really felt like I was soloing Roshan while juggling between two tank heroes and one support, with health salvos scattered all over the place. It was simply not the kind of experience I was hoping to get. I was hoping like a 3vs1 battle between all the giant mechs going all out with the demon (with all the line units as cannon fodders) but alas, I suppose I have to just live with the three main heroes running around kiting the demon.
The story was good enough, although repetitive. wasn't expecting a demon under the ice, good job for that. but still deep inside me I was kinda hoping I'd unlock a new race, or a new campaign after finishing the main one, just like the good old days of RTS. Please consider that, relic.
Going forward, I think it is only logical to do a meta-map campaign, just like Ardennes assault. I mean, that was like THE best RTS campaign I have ever played in my life. Maybe for the sake of a linear story, you didn't introduce that in DOW 3, but going forward it would be utterly stupid not to. Even back in DOW 1 Necrons (as a playable race) was introduced alongside a meta-map campaign, right? Really loved my OP Necrons in dark crusade~