I spent a weekend playing Colony Wars with my friend Zac and at this point I think I've got a sense of how it plays out. So let me tell you about it.
If you've been playing the original Star Realms, then you've probably discovered by now: the Machine faction (red) is incredibly strong. Even in comparison to all the card draw effects of the other factions, the consistency the Machine faction can provide is incredibly strong.
So I'm pleased to say that they've started balancing it far better in Colony Wars, with cards only allowing players to scrap (exile) cards only in their hand or only their discard pile but not allowing the option to choose either.
That helps hamstring the faction just a little, creating some tension: am I going to get rid of an unused resource in order to gain consistency later, or am I going to hold on to gain more this turn? It's an interesting question and the game is better for it.
It's still really possible to go very, very big early on and blow your opponent out. Scrapping a card for cash can provide the kind of lead in turns 2 or 3 that can find an opponent sucking wind for the rest of the game.
That said, once you get the hang of things, games can become tense affairs that pass by very briskly. Losing doesn't sting so bad, as you just shuffle up for the next game and take another swing. In this sense, the better qualities of the original Star Realms set is perfectly preserved.
If you haven't tried the game and are interested, I say give it a go. If you've already got the original, I think Colony Wars provides balance and enough diversity from the original set to invest in.