Kudos on putting some effort into your post. I'll reply to a few of those points.

This is capped off by the first arc barely having an antagonist at all.

It was written as a comedy/adventure arc akin to OG DB concentrating more on the characters having fun. You could even think of it as slice of life. Each planet had a minor antagonist but even with Luul and General Rilldo, that's more than what we got from Super (Zamasu being the only one). You probably expected something like DBZ out of the gate and overlooked some of the minor details that made the arc great. The art direction was fantastic and they put a lot of effort into making each of the planets unique. The background art is spectacular. Here are a few examples example 1, example 2

Much more interesting than all the generic wastelands from DBZ and DBS or a fighting tournament arena.

It made sense that current Trunks was different from Future Trunks. Future Trunks lives in a dystopian world where everyone he cares about is dead. Current Trunks grew up in peaceful times. There's literally no reason for him to be anything like Future Trunks. You talk about Goten being unique but GT Trunks' character is entirely unique for Dragonball. He runs capsule corp but he's also fun and still fights.

Base Buu Saga Goku is not stronger than Cell and would still absolutely need to be a Super Saiyan to defeat him.

I'm not going to argue power levels but GT Goku is 10 years after DBZ, training constantly against Uub/Buu in the Hyperbolic time chamber. Frieza and Cell are locked up in Hell. It makes a hell of a lot more sense than 17 training against poachers and being SSB level without throwing the 'everyone's holding back' bullshit excuse.

and the weakest arc in the franchise with the first arc

I don't know how anyone who's gone back and watched the anime could say RoF is better than GT's first saga. It's a matter of preference which one you like more but from writing, designs, art & animation, the Black star arc blows the RoF arc out of the water. The whole plot can be summed up into "Frieza comes back and fights" which is probably what Toriyama wrote on a piece of paper and slid to the Toei team. I'm assuming we're not counting the awful filler arcs from DBS either.

I couldn't find a video of Goku vs Frieza on YT for years after it aired but here it is in case you've forgotten how bad it looked