Frankly, I'm glad Voyager didn't do a full circle ending.
After TNG & DS9 did it, having Voyager do it would have been too predictable IMO. I kinda like the ending gave us the unexpected.
I would have given "Endgame" 5 more minutes and have Janeway giving her first Adm. log by telling what happened to the crew after Voyager got home. As she was narrating it we'd see those events with the characters take place.
While I think 7th season might have been too late for the story, I've always wanted a ep. where we saw what Neelix' life was like on Rinax. We never got to see exactly all he lost. I think we'd learn to feel sorry for him if we knew what life was like for him before he lost it all.
I would have(if the actress was available) built up a romance for Chakotay with the blonde woman from the Equinox. Through her we could of been filled in on the rest of them without having to bring those actors back. It would have developed Chakotay's character and been a more satisfactory ending for him than hooking him up with Seven.
I would have done one more Kes story. Her getting back to Ocampa and find out hey had become slaves to the Kazon It also would have been a great way to revisit Seska's child and he be the new Maj. His Cardassian cruelty is what kept the Kazon in power by using the Ocampa as forced labor. I'd have Kes teach the Ocampa to us their mental abilities and wage war on their slave masters. I would have the ep. end with Kes' death but her legacy would live on in Ocampian culture.
I would have the Vadwaar return and turned them into desperate terrorist. I would have done a story were they mirrored the Maquis but unlike the Maquis being freedom fighters, they be more like Cardassians. Terrorizing civilizations for their survival.
I would have done a Harry/Tuvok story where Tuvok takes Harry under his wing allowing Harry to finally mature and earn the rank of Lt.