You 100% do not want to spend $60 on this, if you mainly want to play a good campaign.
DoW3 is a major departure, from previous entries, as it pertains to the the campaign. It's downright sad, compared to DoW2. No more wargear, no loot, no level progression, no skill trees, no selecting branching missions. The only reason to play it, is because it unlocks stuff for the multiplayer.
Makes me ask: Whut da fook haz Relic been doing, since the DoW2 release, in 2009? The Retribution expansion came out 6 years ago, and this has launched in a much worse content state, than even vanilla DoW2.