Science fiction has a lot of ways to get around. Star Trek has its warps, its slipstreams, its spore drives. Haven’t seen Discovery? Don’t ask. But the spore drive kind of works if you ignore how silly and OP it is and pay attention to the good stories they tell with it.
My universe has three modes of getting around. The “rules” are set by the series and stories they’re told in, but they have three general classes of speed bound to common sci-fi tropes: warp, hyperspace, jump.
Warp is…warp. Big bubble around the ship. Ignores the whole business of e=mc^2 so you can tell good stories. It’s the slowest, but has no real downsides beyond needing a much sought after resource I haven’t yet defined.
Hyperspace opens a window in subspace, also poorly-defined, and moves through it. I think of it like hyperspace in Babylon 5, or the Nether in Minecraft.
Jump also depends on subspace. Jumping damages subspace on both ends and prevents everything except warp and sub-light speed communication. Gates don’t have this problem, but damage to subspace also affects them. Jump drives are huge and can only be mounted on really big, expensive capital ships. That means you can’t roll in with your fleet, stomp someone, and roll out. You risk a bunch of angry people chasing you at warp with what’s left after planetary defenses tear your fleet apart.
Gates are self-aware and completely independent. They allow instant, consequence-free travel by consent for ships (space) or people (planetary) of any size, but their AIs are seeded with protagonist values. They generally won’t allow invasion forces through. Somehow, I don’t yet know how, the Bulwark figured out how to suppress the AI. It’s hard to do and has some limitations I haven’t yet worked out.