I've actually enjoyed my time with DoW3 so far. There are some glaring issues with unit selection that are being highlighted already, so I'm going to throw some new things into the mix.
I think the game could do with more early game defensive options. I know the unit count is rather large and listening posts are a thing, but I find defending points a little tedious. It's so easy to outflank a lane and overpower a small point if the enemy player is concentrating his efforts elsewhere. I think limited turret options should become available and would add some extra time to the early game for back-and-forth engagements.
Turrets are a staple of RTS's due to their ability to hold a point. In DoW2, I found the strategical positioning of turrets a boost to the early phases of the game where a player may use them to keep a point defended for just that little bit longer to allow time for reaction. My reactions for certain aren't terrible, but sometimes I can find myself overwhelmed.
Perhaps the game mode isn't suited to it - In which case, I would suggest adding turrets for future game modes more suited to an annihilation gameplay style, or even a take and hold gameplay style. The point isn't to make turrets the end all and be all of defense, but as an OPTION to allow players who enjoy a slower gameplay style to have a fighting chance. On top of that, it would mean that in a lot of situations a complete snowball wont happen for one side if the defending players can defend at least one point.
Hopefully I'm the only one with this opinion, but discussion is vital. Listening posts are pretty easy to shred with a small force currently, I've managed to have a single assault marine squad take out listening posts pretty quickly and its a shame to punish players for the fact that the game can be pretty hectic by design.