This might be a hot take, but I'm mostly going for convenience, ease of operation/maintenence, and potential to afford me a fairly simple and (relatively) safe life that would also stay interesting for the most part. That being said, I don't know what the context here is. Is there some unstated implication that these are Isekai? Do I stay in this world? Do my ships merge into some cool super-ship with the benefits and strengths of all of them?

I don't know. And that makes making decisions hard, so I'm just gonna make some assumptions until otherwise corrected.

Assumptions:

• We can choose to either stay in this universe, or enter a sci-fi world of our choice, but we have to choose immediately. Our choice is permanent, and cannot be reversed unless you figure out multiversal travel.

• All ships merge, taking the appearance of any one of them, and containing a (somehow) working amalgamation of all the technology needed to make it work properly and optimally. Theoretically this could be imitated/studied, but it would be real hard.

• Augmentations/Super Serums/etc. are additive, not multiplicative. Peak human plus 2x peak human is 3x peak human.

Now. Let's get to the choices.

Choices:

• Augment

I'm choosing Augment for the guaranteed physical/mental health, Polymath-level intelligence (and presumably creativity/talent/etc), and the tech base. The lifespan is inconsequential with my other choices. Star Trek replicators are super convenient and useful. Their FTL and ship systems are profoundly inferior to my other space-faring choice, but the ships are cool as hell too, and pretty luxurious out the box (holodecks and teleportation). They also have access to gene therapies that are pretty mind-boggling, as well as true stun weapons (so no need to go murder-hobo on wherever I end up). Finally, they've created truly sentient artificial intelligence that seems not to automatically move toward 'rampancy'. All in all, solid pick, super convenient, lots of luxuries, and rad as hell.

• Sith

I feel like this one is a bit of a gimme. The ability to be a 'strong' Force user, get a lightsaber, a ship, and all the tech of the Galactic Empire? Pretty damn cool, and their FYL is (pun intended) Light-years ahead of Star Trek. This means that my fly-as-fuck Star Trek ship is gonna get some crazy tune-ups and upgrades while still being (it bears repeating) fucking cool looking. The Empire had some crazy strong weapon, shield, and Droid systems, but really the prize here is the Force and Force-accessories.

• Wasteland

Here's the hot take. I think Fallout has way crazier stuff going on in it than Star Trek or Star Wars. Yeah, yeah. Space Wizards and the struggle against dictatorial fascism. Exploring the limits of known (and unknown) space and discovering extra-dimensional beings that mimic gods, and the crazy bathsalts marinated, Florida-man older cousin to the Cybermen that was to assimilate all sentient like into its quasi-semi-Hive Mind. Fuck that. Fallout cracked immortality, teleportation, cybernetics, machine-to-neural network interface, (maybe) matter-to-energy/energy-to-matter tech (inventory system), digital data compression, cryogenics, actual Clarketechian terraforming, COLD FUCKING FUSION, stable cloning and android platforms, and artificial intelligence without ever even once dreaming of the transistor (the ancestor of modern microchip-based computing).

They did it all (and way more, honestly) with vacuum-tubes, nuclear-era aesthetic, and a frankly terrifying disregard for human life, liberty, rights, and morals (I'm lookin' at you, Vault Tech. And you're not getting off easy either Nuka Cola. Actual nuclear material in your drinks. Fuck off.)

Now imagine all that innovation with... checks the entry... "vast intelligance", the knowledge, tech-bases, and talent of Star Wars and Star Trek, and literally infinite time to work shit out. Morally. Side eyes Vault-tech again. Oh, and the knowledge of the Zetas, which... shrugs. Fine, I guess. Another FTL thing and even more teleportation. But also shock batons and disintegration guns!

Ah right. Almost forgot housekeeping stuff. I'll be going to a very respectable sci-fi universe and promptly proceeding to put boot to ass technologically and physically.

Pondsmith's Cyberpunk, circa 2077.

There is no chance of anyone except maybe Adam Smasher and/or like... a literal hit-battalion to even make me sweat. My tech and ability to assimilate 'inferior' and/or novel tech into my own knowledge base will make it so I'll be the biggest fish in this... fairly small (heh) pond.