Rushing is the cheapest thing in the world, as we all know. So to remedy this, they should implement invisible walls between bases that no unit or weapon can pass through for at least 10-15 minutes so we can all safely build our units and buildings without fear of rushing.
Also, warthogs are overpowered, so just take them out of the game. Completely. That way the UNSC has one less unit to fight with. And while we're at it, take away covenant leader powers. And the arbiter completely. He's too cheap as well. Oh, the scarab has to go. But not out of the game, just make it more humanized, and give it to the UNSC. Name it the Magnificent Basterd (sp?) as well, and give it the ability to spawn spartans for free.
The disruption beam has to go, since it is useless now that covenant leader powers are gone. And give the UNSC a 60 pop cap. Can never have too many grizzlies ;)
To balance out the sudden downsize of the covenant, make Professor Anders a covenant leader, and give the UNSC the Master Chief. She can run about now, casting Frost Nova on units around her (being not a true "Covenant" she keeps her powers, to keep with some storyline somewhere) costing 264 mana per cast, freezing them in place for 15 seconds, unless they have the sprint upgrade in their talent tree and can break out of it once every 5 minutes. Instead of marines, the Master Chief gets Spartans, with no build limit. Also he starts with a free Magnificent Basterd (sp again?) but at the cost of all but 100 starting resources, not too bad though, since no one can attack for 15 minutes.
Oh, and grizzlies are half price, and build twice as fast now. And Sgt Forge's heavy supply pads cost as much as a normal supply pad. But he doesn't get carpet bombs anymore, cuz those were useless anyway.
If this doesn't fix most people's issues with the game, I don't know what will. Please respond with feedback, as I am open to all advice for the new and up-coming Halo Wars. Thank you.