Unfortunately, it looks like Dawn of War III won't be for me. While many Dawn of War I fans did not like that there was no base building in Dawn of War II, for me that was actually the main reason why I enjoyed it. There are two reasons for that
1. I just suck at regular RTS games. It's too much going on at the same time for me. I can only focus either on my base or on my troops in battle, so either I micromanage a battle and meanwhile I don't produce any more troops or my base gets attacked, or I focus on my base and my troops fall like flies elsewhere on the map. So in DoW II I enjoyed that I could fully focus on my troops and detailed tactics.
2. While the base-building in DoW I didn't feel too weird, the purely tactical gameplay in DoW II just felt a lot more like the tabletop to me.
Now with the strong focus on heroes and their special abilities in DoW III, it looks to me like even more multi-tasking might be necessary (as I'd have to focus on heroes, line units and base-building / production all at the same time).
I also liked the strong RPG part in DoW II a lot. I don't know how much of that will be kept in DoW III, but with a much bigger army, it can't play as big a role as in the previous installment.
Then one detail I found really strange watching that video was the new cover system. Instead of using the terrain as cover (like in the tabletop and the previous DoW titles), now they have that weird system of cover being some kind of shield generators you have to capture. That has nothing to do with the tabletop at all, and it just looks weird.
Dawn of War III will surely be a good game overall, but I guess I'll stick to the previous one, which just feels a lot more like a real-time Warhammer 40.000 to me.