I think Vegapunk and Elbaf centric arcs are entirely relevant and need happen. It's It's possible they are even part of the same arc and Oda pulls another "mega" arc with Elbaf like he did with DR. We have 2 Supernova to focus on, Bonney and Urogue, who are by far the most mysterious pirates out of the 11.
Bonney is tied to Kuma, who in turn tied to Vegapunk. We also haven't seen Smoker and Tashigi in 200 chapters, and their last known location was at Vegapunks lab, they weren't even present during the Reverie. Since then Vegapunk has been repeatedly teased by Fujitora, the SSG, and Orochi's desire to have him. Something big is happening here.
Urogue is even far more mysterious. There's nothing really pointing him to anything, but if I had to guess, Elbaf would be his likely appearance. I've always had this big feeling that Elbaf will be this huge lore dump about OPs world, and Urogue will tie that lore between Giants and Sky People (just a guess).
There's far more that would go into this, namely the 2 remaining Yonko and any other major faction involved, but I think these 2 are the prime candidates for what is next. Then following this with Lodestar and Laughtale, you build up to the final war. That's my thought process anyway. I don't see Luffy jumping straight into the final war right after fighting Kaido. There needs to be a lot of buildup to get to that point, knowing Oda. It took him 300 chapters to build to Wano (which is why i doubt the whole 5 year timeline comments, which is now 3 years and we are still in Wano lol)