A game where you're managing a fairly small mercenary outfit, with both moving around in a strategic layer and fighting in a tactical layer. Sorta like Battle Brothers.
Except rather than a flat map, you're moving around on a spherical planet, and can use your own craft or catch rides up into orbit, and to other planets in the solar system, and to other systems by traveling through wormholes.
This is important because units in orbit can look down on the planet, sending you intel, or have reinforcements deorbit and drop directly into your fight if you need them.
This is also inspired by Cortex Command, so not all of your units need to be independently acting humans, but can be remotely controlled robots and such as well. Of course, having your combat units rely on radio signals is risky, and makes electronic warfare a consideration. This also can be relevant when trying to communicate with units in orbit.
Combat between space ships is also possible, but rather than having its own tactical layer it all takes place on the strategic layer, with missiles and other projectiles traveling like any other craft on orbital trajectories. If an unarmored craft gets hit by something, it'll almost certainly be destroyed along with any crew, so keeping valuable employees in space can be a dangerous proposition if the enemy has space presence as well.
Orbital bombardment is possible and very powerful, but expensive due to the fuel requirements of deorbiting the projectile. While it's possible to kill things on a planet from orbit with no risk of counter attack, it might not be profitable, forcing you to land ground units if the target of your contract has defenses against orbital weapons.
Everything in space has its orbit simulated, and that matters for how things go on the ground. If you start a fight on the ground and your spy satellite is over the other side of the planet, you're not getting intel from it. If you start that fight with the satellite in place, you'll only get intel from it as long as it remains over your head; if the fight takes too long, it'll move out of the way and you lose your overwatch. If your spy satellite is in an equatorial orbit, you'll never get any use out of it if you're fighting near the poles. If your satellite is in a polar orbit, you might need to wait a full day before it's in the right place.
Basically, I want a fairly realistic depiction of how space travel affects combat strategy.
And also a world map that's actually a sphere, because that's cool.