This ranking will use the characters English names, it will not include their Digimon and will be subject to change as I go through the Digimon Tri series, so let's begin.
Tai
The very definition of fiery leader and if he stayed that way, his ranking would be pretty awful but something changed at the beginning of Tri, he discovered the real weight and effect of the damage caused by the fighting Digimon, and while Matt was quick to call him a coward, it's a sign of growing up and in character for him considering that his selfishness has caused harm in the past, how Tai overcomes this will be interesting.
Matt
I've never liked Matt, he's so temperamental that you have to question why he has the Friendship crest, this hasn't exactly exited his system come Tri and throwing in a love triangle that involves Sora hasn't helped.
Sora
A lot of people didn't like her shedding her tomboy persona from season 1 but I'm in two camps with this one, her arc was reconnecting with her mother which was fully complete by season 2 but I also see her losing alot of her personality come Tri as her conflict is all romance with her friends.
Izzy
He hasn't changed at all, but I like how his social awkwardness is more on show in Tri, but yet his ability to produce tech on command is still a little too convenient.
Joe
He's somehow become the least reliable of the team in tri but at the same time, he's older and at a point where his actions have changes to his life, this especially prominent where he's actively failing exams, he brings up a good point about the whole Digi-Destined and why they have to be the ones to solve all these problems when adulthood is closer than ever.
Mimi
She started as the team Scrappy but is now hands down the most fun character in Tri, you could argue it's the American effect, but it works for Mimi as her arcs did nothing for her in the early seasons and this more expressive happier Mimi is very much welcome, her approach is rough but it works for Mimi and has made her the most evolved character.
TK
He went up massively in my estimation when he beat the crap out of Ken, now he's Matt's foil as he looks and acts way more mature than his older brother.
Kari
She's a fan favourite and a healthy balance of tomboy and feminine, she's largely unchanged in Tri but doesn't need it.
Davis
Worst protagonist ever, he's dumber than all his contemporaries combined, that includes people like Tyson of Beyblade and Ash of Pokemon, I've never seen a character so content with being that way, he's a waste of space and made season 2 such a weak series compared to even Digimon's worst.
Yolei
Yolei is at least salvageable, a balanced character with a hint of silly and brutal honesty, she's what Mimi is now in Tri and what Sora was in season 1, probably has the best traits of both those characters.
Cody
He's boring.
Ken
A villain turned hero was new for Digimon at the time, but I found that compared to his contemporaries, he really lost alot of his personality when switching sides.
Meiko
Meiko is an interesting one as there really isn't a shy girl amongst the Digi-Destined, so she fills a personality not been done before, however her role becomes redundant after Meicoomon is revealed to be causing all the disturbances.
Tai-8.0
Matt-5.8
Sora-6.3
Izzy-7.0
Joe-7.0
Mimi-8.9
TK-7.9
Kari-8.0
Davis-1.2
Yolei-7.1
Cody-3.0
Ken-6.0
Meiko-5.5
