What systems are on your 'I want to run but probably never will." list?
I've talked about them at length in this thread, but I'll go over them again since you asked.
The big one for me has to be Castles and Crusades. Every video and forum post praises that system to hell and back. But nobody actually wants to play it. This is basically true of most OSR games, but Castles and Crusades is the one I've heard the best things about.
Some systems I was curious about but gave up on.
Years ago I was really interested in the Cypher system. I wasn't a fan of the reliance on disposable gadgets, and I've forgotten almost everything else about it, but I remember the system seemed interesting.
A friend of mine keeps telling me to play Spycraft 2. The appeal of that system seems to be the broken builds you can make, but I'm not a fan of how everyone has a pre-defined role and is useless outside of that.
And furries have shilled IronClaw to me a bunch of times. Seems almost like Savage Worlds in many ways.
The main thing for me is less systems, and more settings.
Cyberpunk 2020 and GURPs Cyberpunk sound like a great time, but people only want to play Shadowrun. I don't like how the magical bullshit dilutes the cyberpunk elements and how it's easy to break the game with certain things like Riggers.
I want to play a mech based setting, but everyone only knows MechWarrior and that game scares away everyone. The only other systems available are either autism simulators, rules lite story games that lack in crunch, or seem incomplete. Tiny Frontiers (the old edition) is the closest I've found to acceptable, but that leans a bit too close to rules lite and incomplete. Fates also gets name dropped a lot, but I completely fail to understand it.
I could go on by mentioning a whole bunch of stuff (RIFTs, super heroes) but the final setting I'll mention in this post is Al-Qadim, or any desert based setting really. I don't care if it's medieval fantasy or 1930s Indiana Jones adventure. It's just raiding pyramids, fighting mummies, and the whole general aesthetic appeals to me, but it's largely ignored in favour of Tolkien medieval fantasy.
I've found myself drawn to older systems.
I'm not. I prefer "new" systems. I put "new" in quotes because systems like Savage Worlds or Castles and Crusades apparently go back a ways. "Old" systems and modules tend to be hard to read and poorly edited in many ways.
The problem with many "new" systems is they tend to be pointless. The glut of woke PbtA based games that add nothing of substance have been condemned a lot here, but I also I don't see the need for another d20 + modifier DnD clone system. They might move minor things around like making AC ascending or descending, but I fail to see the point.
Another problem with "old" systems is math bloat. Or is that "new" systems? Whatever, spending 5-10 minutes every roll trying to figure out bonuses and penalties, or having to sift through thousands of feats and recalculate a bunch of formula every time I level is something I don't miss.