Let me put it like this :
Reach the system for an invasion. Take care of a couple of fleets while reaching the planet itself. Then blow up the station and it's last remaining fleet. Here ends "vanilla" and you work begins. Vanilla would have a text only management of the attack and that's it. You win or you lose, but the event ends here. Couple minutes, tops.
So here is what you added :
On a custom tactical screen based on the intel menu you launch the invasion and manage the troops (resize some units, move them to engage, use a commander skill). Give the order to attack and back to space view.
Then you have to hold. Other planets in the system are gonna launch some space enforcers too and they'll be coming your way on full burn. The invasion is progressing nicely (tactical screen again to assess and manage the troops and use skills) but you need to hold this space or the other guys will counter invade (I suppose ? Never got to actually see it so maybe I'm extrapolating too much). And anyway having space superiority lets you unleash skills to help the invasion. You need to hold. While still taking care of the ground pound you manage to repel a couple more fleets by the skin of your teeth : CR keeps going down fight after fight and can't max back before the next so space battles become harder and harder. And not only does that wreck your supplies but you also use a lot of it for the ground skirmish. So supplies start running out. This is becoming tense.
After a couple minutes waiting for that big fleet that'll terminate your endeavor (and it's coming, you know it's coming), after a last round of guerilla warfare you hear a powerful cheer from the surface and the planet is yours.
You can land for R&R and look at the spoils of war. And at the casualty count. It took around 20 minutes of nail biting successive fights and army management.
I know I'm explaining his mod to a modder. But I really clicked with your mechanics lately, and wanted to share how it feels. And it feels great.