My favourite game that never made it big, and almost nobody has ever head of is EMPEROR OF THE FADING SUNS for PC.
An old empire management and intrigue game. Where you begin as one of several noble houses. Starting off with choosing various perks and penalties. Such as being INBREAD. Then you try to maneuver yourself into a position of power through periodic Regent elections, or swaying the favour of the church or merchants guild. There is a tremendous amount of tech research and unit variety.
At this point I think I should mention it is something like the year 20000. And we are fighting over an empire of dozens of star systems. And not only must you battle in space, and transport units or resources between worlds. but then your competing for ownership of all the worlds on the ground level. With naval, air and ground forces. Added to it are two NPC factions, a high-tech xenophobic alien race. And a viral mutation gone rampant that is spreading through physical contact among the worlds. And YES, your own units while in combat may be converted to mutants.
There were several issues that never got properly patched. However die-hard fans have created a number of unofficial mods to resolve those issues and better balance several issues.
To date I still love to play this PC title from 1996.
If you love a 4 dimensional resource and empire building RTS, that does not emphasize military conquest as your only option. EFS is a good choice. I am biased, and provided you patch with the unofficial patches. I would give it a 3.5 / 5
But regardless, I love this game and still play it religiously. Right next to my Tie Fighter game.