I keep going back to this idea of running a campaign heavily inspired by X-Com and similar tactical RPG video games. To be specific, I mean highly detailed grid based combat missions, with base building, gear upgrading, character advancement and some "story" advancement happening in between. (I know some folks will balk at X-Com and this setup being an actual RPG, but I am not realliy interested in that debate.)
My question is which TTRPG will best support that play loop? I kind of want to go with Savage Worlds, except SWADE is not very granular with gear, meaning the research and upgrade part of the loop is not going to be especially engaging. I am sort of interested in seeing if Starfinder2E would work, but it might be too much.
Thoughts?
Just as a note: merely naming a game won't do me a lot of good. Please explain how you think it would work well. Also, games with fan licenses or even open licenses are a plus.
If you can find him, Hemlock/Max Wilson/FormerlyHemlock was trying to do much the same some time ago. I think he started wanted to do so with D&D 5e (converting it into a computer program as an intermediary), but decided finally that it was the wrong game for the task. I think he ended up going with GURPS (although who knows what it might be now). I lost track of them between covid and shifts in the boards we favored. We didn't always see eye to eye on positions or behaviors, but I was always impressed with the amount of effort he put into his gaming and thinking-about-gaming (much like Snarf, he put more time and energy into individual gaming topics than I have time to spend on gaming as a whole).
Either way, I would suggest GURPS as a reasonable ruleset for this type of endeavor.
It supports gear-porn fairly well in general (gives money and encumbrance actual in-game importance so you can't have all equipment options; things like weapons have a half-dozen or more different qualities so there isn't a simply-best rifle, etc.).
There are huge lists of situational penalty charts like cover and wind and lighting, as well as complex rules for things like aiming, snap-shots, recoil, cover, etc. Things like unaimed full-auto shots are sufficiently penalized that the actual (ruleswise) optimal strategy isn't to eat the penalty and try to get as many attack rolls as possible (something I've noticed isn't always the case for combat TTRPGs). Instead, it leads you to make decisions like
'Here I have at least 3 seconds to aim with my scope, but my angle is bad and I'm far away. Do I take the shot now, or move closer -- potentially getting a better shot, but risking them spotting me and diving for cover (meaning at best I take a low-accuracy snap-shot on the run before they can)?'
The game, overall, is very good at low-res, high-granularity simulation to a real-world-looking world. I recall going over the (3e) rules with my gaming group bitd when we had way too much time on our hands and determined that the reported 'realism' of the game was really more 'internal consistency.' That said, it generally has rules (and covers territory) that lead to real-world-like results (encumbrance really slows you in combat, even a slight injury really hurts your ability to hurt your attacker, cover is awesome, knowing exactly where your opponent is is a major part of tactical task, trying to minimize penalizing situationals like wind and distance and light-level issues are really important, etc.).
The one thing I will caution is that the character creation system maps to character effectiveness (particularly in a combat-focused game) only very broadly. It's an artificial economy, and obviously more points are better than fewer (and because you have a budget, your can't get everything you want). However, there are going to be optimal selections and bad choices and so on (each edition, genre, and tech level being different; especially with regards to how much being rich/able to afford better gear has an outstanding impact).