RPG

Best for what purpose?

There's no universal "best" because different people want different things from their spaceship combat games. Myself I like quick resolution and simple record-keeping so I always kit-bashed something with the old Starfire wargame to warp it to the RPG setting. If you're not into kit-bashing, though, that's not going to be "best" for you.

For spaceship combat that was tense as a suspension bridge truss, the one that was made for Traveller:2300/2300AD was really, really good, but it was very much glued with cyanoacrylate to the setting.

The original Book 5 for Traveller had a ship combat system that was very much about capital ship combat in large fleets (and could barely scale down to smaller conflicts like individual ships). It was "perfect" for that kind of thing, but again was glued to the setting (albeit more with some contact cement rather than superglue).

The Jovian Chronicles (game, not Mekton Zeta supplement) space combat system was rather nifty and came with a nifty spaceship design system (albeit one that had a "dreaded" cube root in the construction rules that made people panic). And while it was made for a setting, it was much easier to kit-bash for other settings.

For more generic games, if you want the scope and glory of space opera, the game, well, Space Opera is hard to beat. It's an old design, so filled to the brim with odd, crunchy, ornate bits, but it was a whole lot of fun when I played it. Just ... be ready to fill out a lot of papers and roll a lot of dice many, many times.

Star Trek Adventures, hands down.

I mean it's not as it is particularly brilliant, but unlike most games it don't go to usual extremes of being boring extra chore with a lot of specific rules, minigame without any depth or something so integrated with normal mechanics that there is no different between capital ship combat and a fistfight in bar. It's based on normal rules but somewhat modified because those are usually big ships fighting and thus pretty immersive and at the same time still feeling distinct.

I feel like Starforged can feel pretty cinematic, particularly for a dogfight style encounter!

I've been thinking about this a lot. And not just for space combat. Naval combat, too. I don't have a good answer. I think a single-person fighter dogfights could be done almost the same as person to person tactical ranged combat. Maybe not naval here - tactical Optimist or canoe battle. ;-P Larger ships, though, are either going to be very abstract, if you're the captain giving orders, or over-zoomed in if one following orders. A partial way around it is to treat the ships as the characters for the fight. Easy for solo. Takes agency away from everyone but the captain in a group. Which is probably realistic, but hardly fun. Even so, you can have the gunner rolling for shots fired, navigator rolling dodge, etc.

I've been avoiding (solo) games with ship-to-ship combat, as much as I really want to, because I haven't felt able to do it justice, yet. I suspect I'm going to end up somewhere between Pirate Borg and Worlds Without Number ship to ship combat, but playing as the ship, once I finally do bite the bullet.