I feel like this game does an amazing job of making the mechanics embody the races they are for.
Orks are a numerous green wall where if you let them build up the numbers and hype themself into a waagh they feel completely unstoppable and many waagh rushes I have been on the other end of make me say jeez there are waaaay too many of them what the heck could even stop all of that!
Eldar are fast elite fighters who use hit and run to dominate and wear down opponents. When played well they overwhelm opponents with speed map presence attrition and quick ambushes that other races have a hard time pulling off or keeping up with. Such a fun and interesting play style.
Space marines are tanky adaptable elites who can stand up to a huge beating but generally seem to put out less damage than other races per money spent without unless they rely on tactically specialized strikes to counter the type of foe they encounter. (flamer to put out a ton of burst AOE damage on a melee horde) (drop pod with guns to spread high AOE damage on those ranged infantry that pump out much more dps than SM if you try to close in on them) (assault marines to jump in to tie up specialized units that pose the biggest threat to your strategy if left free to fire.) (drop pods that damage armor when they land, aka another way to deploy a surgical strike and take out the most dangerous parts of enemy army asap) Then to help them survive to implement these tactics and make them that much tougher to take down a banner to shield and heal the army as each unit tries to execute its specialty job.
Overall each race feels much more defined and unique in this version of DOW and I think relic deserves some recognition for doing a good job on making them all unique and much different to play.