Personally, I think that the actual ending to Z, Goku flying off with Uub to train him, is just fine. Probably won't ever get a better ending for the series/franchise than that. And 10 years is honestly a pretty long time. No reason that Super's story can't be told within that length of time. I get the argument that knowing that everyone lives might take something away from a story and it's a fair one. But if we're going to go with that argument, then nothing that's happened over the course of Super thus far really mattered anyways. For me, it's just about making the writing good enough, so that the story can continue to stand on its own without that threat of the unknown being present. They mentioned The Hobbit. As someone who only read that book after reading Lord of the Rings, I already had a decent bit of information as to where things were going and knew that the main character, Bilbo Baggins, was going to make it out of things just fine. In fact, I knew that he'd be better than fine, since he'd go on to live and be fairly prosperous for decades afterwards, even surviving until the end of the War of the Ring. However, excellent storytelling made it so that I really never cared. The characters and events kept me interested throughout the book and this is something that's actually occured with the story across multiple adaptations now.
Definitely do NOT think that they care about GT or aligning Super with it in the slightest. Toriyama clearly didn't, because the original Battle of Gods film basically spat in the face of GT when it introduced SSG. Since then, things have just diverged more and more. I think that some fans of the franchise, who do support GT for their own reasons, have then just really been too...rigid or unwilling to understand the concept of a franchise not having just one specific universe that is "canon". To me, the word really doesn't matter except when you're talking about things like "Does X-Character/Concept exist in Super" or something. Digimon, Tenchi Muyo, and various other anime have been doing this kind of thing for years without there being an issue.
Only reason, in my opinion, for Super to go past the ending of Z is if you want to bring in Uub. However, there needs to be a concentrated effort towards making Uub a, if not THE, main character in that case. Because right now this is the Goku and Vegeta show. If Uub's just going to appear so that he can become a part of the background with everyone else there's no real point.
