This has kinda been on my mind lately so I’m just going dump it here. (Also going to use a bit of fanon that I really like in this)
Phantom Planet turned out to not be real and just a test for Danny made by Clockwork and the other guardian ghosts. It was to test his ability as a leader and see if he was able to get the ghosts and humans to work together. They don’t tell him what it was for though.
Danny starts to learn more about ghosts and the ghost zone and learns there are better ways to get the ghosts to stop attacking then blast it until he can shove it in the thermos. Of course he also learns that’s the only tactic possible for ghosts like Skullker who won’t listen.
Danny becomes friends with some of his enemies like Kitty and Johny (after Johny gets the sexism beaten out of him and he starts treating Kitty right) and starts helping them cope with their obsessions in a less dangerous way, for both the humans and them (help the ghosts become a little less crazy)
There is better development with Danny and Sam becoming and being a couple. This time with less third wheeling Tucker.
Some Tucker and Jazz based episodes because they need some attention.
Dash sees Danny’s battle wounds and thinks he’s being abused. This is how Danny finds out about Dash being abused and helps him as both Fenton and Phantom. Dash stops being a bully and he and Danny become friends though he doesn’t learn Danny’s secret until much later.
Dani helping Valerie reconcile with Danny and he eventually tells her his secret. She is then welcomed into Team Phantom.
Vlad is severely injured in a fight and is forced to transform back into his human form in front of Jack. This spurs on a redemption ark for Vlad.
After Vlad’s redemption Dani (and if I had my way the other clones) going through an emotional struggle with still being angry/fearful of him despite him regretting what he’d done and trying to make up for it. Eventually, there is understanding and forgiveness and Vlad gets the family he always wanted but was too blind to see he had.
Knowing his parents know about Vlad and have accepted him Danny gains the courage to tell them about being Phantom. There are hugs.
The guardian ghosts eventually tell Danny that after beating Pariah Dark he is now the future ghost king and PP was a test to see if he was worthy.
Danny turns 18 and is about to be crowned king of the ghost zone when Dan escapes the thermos and crashes the coronation. He then steals the Crown of Fire and Ring of Rage to wreak havoc on the ghost zone and human world. Danny has to rally all his allies and even a few enemies to help defeat his evil future self once and for all.