New races
Vostroyan Firstborn, Blood Angels, Thousand Sons, and Tyranids.
What you see is what you get
Weapons do the same amount of damage regardless of what unit is carrying them. A heavy bolter carried by a space marine is the same as a heavy bolter on a leman russ. Explosive weapon aoe matches the visible blast that it causes. Weapons with multiple barrels multiply their damage by the number of barrels they have. ie twin linked lascannons do twice as much damage as one lascannon, storm bolters do twice as much damage as a regular bolter and so on.
Weapons that fire one shot at a time (plasma guns, autocannons etc.) should always fire in sync with the damage they deal. ←- still a work in progress
Pistols do not suffer an accuracy penalty when moving.
Ranged weapons no longer knock down infantry.
Ranged weapons cannot shoot though terrain.
Melee weapons always hit.
No unit caps (on most units)
Most units don’t use squad or vehicle cap or have any limits on how many can be built. There are a few that do for balance or lore reasons, such as superheavy tanks and lost tech like the leman russ vanquisher.
Faster Game pace and basebuilding
Reductions in training time allow rapid army building from a single infantry and vehicle building. This increases the pace of the game and prevents the ai units from getting stuck. All research now requires the player to make a choice between limited options, any research that doesn't has been removed. Together these changes make teching up and building a large army much faster.
Over 50+ Community made maps included
Armor works in a logical and consistent way
A weapon will do full damage to the armortype its designed to defeat and full damage to all weaker armor types. For example a lascannon will do full damage to everything, a heavy bolter will do full damage to infantry and reduced damage to light vehicles while doing almost nothing to a tank.
Fewer infiltrated units
Only units that are actually invisible in the lore have infiltration. At the moment these are the tau stealthsuit and necron wraith. All units and turrets have a detection range of ten meters.
Scout units
Each faction has a unit with a sight range of 60, these are: space marine scout, eldar ranger, guard sentinel and assassin, sisters assassins, necron deathmark, tau pathfinder, ork kommando, tyranid lictor, and vostroyan snipers.
How regeneration works
Units no can longer regenerate while in combat, but the time it takes infantry to fully heal has been greatly reduced.
Official GW and Forgeworld units only
No weird homebrew stuff.
Smoother tank movement
Much less stop and go movement, tanks reach full speed and stop nearly instantly. The monolith now moves like a hovercraft and doesn't have to come to a stop to turn.
Aircraft in Dark Crusade
Aircraft have global jump range and instant jump recharge. Some of them can drop bombs on units they fly over. They have all been scaled up and given crash animations.
Lore accurate unit scale
So far the guard, space marines, sisters, chaos, eldar, and thousand sons, have received lore accurate scale. More to come.
Greatly reduced fog on all maps.
Now you can see artillery blasts far off in the distance.
Campaign and multiplayer supported
Normal and hard difficulty now gives the ai extra resources instead of changing health. Hard is significantly more difficult then vanilla dawn of war.
Race specific stuff
Imperial Guard:
Turrets and listening posts have above average hitpoints.
Basilisks have global range but are the most fragile heavy artillery.
No more free intel from the radar scan.
Guard infantry (not ogryns), take greatly reduced ranged damage in cover, but also suffer a larger speed penalty in cover.
Eldar:
Weapons are slightly better then their imperial counterparts.
All infantry (except wraithguard) got +50% speed.
Turrets and listening posts have below average hitpoints, but can be concealed by the webway portal.
Their hovertanks can fly across the map at extreme speed, but their fragility is not forgiving of micro mistakes.
Necrons:
No longer have moral.
Gauss weapons do full damage regardless of armor type, have shorter then average range but above average damage.
Lack conventional transports but all infantry (not just warriors) can now teleport to friendly buildings.
Monoliths now have global jump range. Combined with the above, monoliths are more dangerous then ever.
Space Marines:
The orbital relay and barracks (now called the first company barracks) have switched positions in the tech tree. The orbital relay is more expensive then other races barracks to compensate for the mobility it provides.
Terminators are great against buildings in melee and can teleport back to their barracks, great for surgical strikes like in the lore.
Tau:
Now get access to all units regardless of what doctrine they choose.
Lacks indirect fire.
Railguns now have their own fx.
Thousand Sons:
Slower but more durable then chaos marines.
Tyranids:
Use DoW2 models.
Can consume corpses for resources.
The hive tyrant and swarmlord now have access to their 8th editon physic powers via research.