Amal

I'm worried that Elbaph will be for Usopp what Wano was for Zoro. I remember everyone anticipated that it would be a big personal arc for him and that he would learn about his family and history but it ended being a small mention and an SBS family tree.

It would be awful if Oda wasted Usopp in this arc that's been tied to him for so long

One piece is my favourite story but I would lose a little faith in Oda as a writer if he keeps ignoring Strawhats development

I know he must have wayyyy too much to do and put into the final saga but as a fan I hope he can include some meaningful character development for our main characters other than just Luffy and Sanji

The 'mistakes' you pointed out weren't mistakenly drawn at all. They were strategically placed to clue readers into the fact that the Strawhats were trapped in the Land of Gods which is a giant diorama crafted by Road, early in the Elbaf arc.

The entire Nefertari family is a part of the D clan.

She and Luffy are not related. Most likely, the D. Name comes from being descendants of a particular group/organisation with no familial relation or could have been one family hundreds of years ago that has since been separated by generations.

Viewer dislike towards Amber has little to do with her vocality and more to do with how she treats Mark in the first season. Her arc in season 2 is considerably better but she loses much of her earlier, more vibrant personality.