Hello after an incredibly long silence!
I finally found a game that respectably mimics what we did with GW. It's called (predictably) Starbase Orion.
The cons: It's $7.99 on the Apple App Store. I don't know about other availability. The online quick-grab game is a bit slow. That's about all I've got.
The pros: It's really cool. Like, really really cool. You have different races, and custom-building ability that's fairly balanced. You have planets that have population, buildings, farming, upkeep, etc. It's a neat map of varying size like we had here, except we could add AI players. There's an option for random space monsters who defend systems of interest. Some systems have more than one colonizable planet, and planet quality varies pretty wildly.
Research is cool. You research 1 thing at a time. It uses RP based on the number of researchers across your empire and racial modifiers. You can build research centers and orbital labs to help boost them--after researching them, of course. Probably the coolest thing is that you have to pick and choose what you want to research. Research topics are divided into three categories--military, astrophysics, or civil projects. Within each category, new projects move down a list and disappear if you don't choose them. For instance, this morning I had to choose Research Center II, and the project expired for a building that would expand a planet's population cap. It'll come back around as I knock things off the list, but you can't have everything you want within that category. There's a very real trade-off to be had. For instance, I had to give up Hydroponic Farms II in order to research Efficient Factories I. But I would never have to choose between better farms and say, Nuclear Missiles I, because it's a whole different category.
Battle? Cool. Ships are expensive. But that's cool because you can design them. Based on the class of ship, you have equipment and weapon slots to fill as you choose, from options you've researched. If your fleet encounters a hostile fleet, you have one turn to issue orders to your specific ships--charge, keep medium/long range, target this ship, escort that ship, evade, retreat. If you retreat or lose, non-combat ships like Colony Ships or troop ships will be lost. The battle itself is a 2-d animated slugfest where your ships maneuver, target, and follow your orders. There's no die roll. If the enemy happens to make all his ships target your biggest one, which you ordered to charge in close, the battle can go very differently than if, say, everyone defaulted to keep long distance and target the closest ship.
Planets can have marine barracks, and to take over a planet you have to invade it with troop ships. If the planet wins, the barracks will automatically replenish marines over time. This battle is calculated and not animated. It's basically a subtraction game. You can also bombard planets if they have no Starbase or ships in that system, but it's a fairly high-level research item and can only be equipped on cruisers and up. You can stack them, but the price doubles with every stack.
Periodically you can also get leaders on auction. A planet governor that gives cheap colony ships, or gives a crazy boost to research or population growth. A ship commander whose ship will survive until the very last of his fleet dies, or makes his fleet heal instantly after combat. One commander unlocks a very expensive ship that spawns maintenance-free space monsters under your control. They make a very real, but not insurmountable, impact to the game.
The early game can take a bit to get going. In single player it auto-plays the rounds until something happens--building complete, reached your target, etc. In multiplayer it forwards when each player has gone. Each turn is 0.1 year, and within 3 years (most-of it auto-forwarded) you have some pretty good momentum. Your speed and range from existing colonies is limited based on research, so you can't just build an early fleet and send it across the galaxy to harass someone.
Let me know if you decide to jump. I'd love to play with some people on here. GW round 3!