Dark Matter Drive

[K]

Aren't relativistic kill weapons always a concern even if your space drives are made of magic? The physics of the universe still allow for things to be cheaply accelerated with rockets or other methods to speeds that make any kind of space habitat wildly vulnerable, and probably most ships.

Rail guns are a thing. Rockets are a thing. Hell, with the mining possibilities of asteroids, actual nukes are just a thing since we are talking about the cutting edge of 1940s tech.

My intuition is that the classic sci-fi trope where everything is a reskin of WWII with fighter aces and capital ships and rusty steam pipes are just a thing in all ships is as much fantasy as old man sci-fi from the 50s where rockets got you to other solar systems.

[K]

As an additional note, I think the only way to make the OP's request work would be to set the game in a sci-fi computer simulation. Your characters are living in a programmed and designed universe meant to replicate old sci-fi settings and that's why RL problems don't exist.

The conceit could that they are in-game currency farmers who are trying to sell enough in-game currency to pay their monthly subscription fee.

[angelfromanotherpin]

Aren't relativistic kill weapons always a concern even if your space drives are made of magic?

It depends, but the problem is not that RKVs exist in the setting at all. The problem is that if every ship is potentially an RKV, a lot of dynamics involving who gets to own one and how fleets interact go to unfortunate places.

[Zaranthan]

I think it's been mentioned before, you don't solve everyone owning an RKV by restricting ships, you do it by giving anything large enough to hit with one access to reliable point defenses. If you can reduce incoming vehicles to shrapnel, and have some sort of force field that can dissipate large numbers of small objects like that, problem solved.

[Username17]

Nuclear weapons aren't impossible to build, and for any civilization able to craft vehicles capable of moving through the uncaring void of space, nuclear weapons are extremely achievable. You have to brainstorm reasons why all important bases in your setting aren't blown up with 10 megaton bombs. Once you have answers to that question, the issue of people potentially ramming spaceships into bases is almost certainly passively solved.

You really don't need to come up with tech answers to RKV in most cases.

-Username17

[Occluded Sun]

In all seriousness, consider something like Battlestar Galactica or Star Wars, where no one developed near-lightspeed propulsion system because they have 'jump' drives.