Honestly, I really didn't think about that aspect with Meat!Karkat, but I like that idea. Karkat has always been the "friendship" troll, the one who is always constantly thinking about other people and how to better his relationship with them. Even if he doesn't think about it in the moment, he is always the type to think back on it later. I think a prime example of this is how he is the only one to really bring up some of the trolls who died on the Meteor or who he hasn't seen in a long time.

Like during the whole meeting scene when Aradia and Sollux make their appearance for the first time in front of everyone, Karkat is like "Well who else is back? Is Nepeta gonna come back from the dead? Is she hiding behind one of those pillars? Come on out Nepeta!" and sure you can say he's just joking because he's so flabbergasted by them just suddenly appearing out of thin air, but it has been like 10 years since Nepeta had died from his point of view and he still thinks about her and how she had died T_T And similarly when they're on the meteor during the Retcon, when everyone is reminiscing about their time there Karkat brings up how he didn't exactly dream a lot but that if he did he didn't exactly think it'd be totally awesome to "see a bunch of dead Nepeta's again". Imo, I think he is constantly bringing up Nepeta specifically as a good example of him still seeing all 11 of them as his friends, even if he hasn't seen any of them for well over a decade.

When Sollux calls him up for food (during a war mind you lmao) Sollux is like "hey uh...we're still friends right?" and Karkat is like "OF COURSE WE'RE STILL FRIENDS!" mind you, he also hasn't spoken to Sollux in years but he still thinks of him as his friend despite that large gap of time. So, I don't see why that wouldn't change for Terezi especially since they were really close.

Terezi's in that bad mental state again, where she's being harangued by a person who wants to use her for some selfish purpose or goal, and she has always struggled with feeling like she's actually the competent, suave person she portrays herself as. And Karkat was the first one to tell her, "Hey, you're like really great and awesome you should stop comparing yourself to other people, you're super fucking cool dude." So if there's one thing I think Terezi NEEDS, it is a normal friend who won't quote philosophy to her and isn't using her as a pawn in a weird pseudo-incestuous game between gods (Wow Rosebot and Dirk are so odd lmao pls someone add normal guy Karkat to this dynamic)

And I kind of like the idea of him being a "mentor" or whatever because then he'd just be following in the Signless' footsteps except this time he's like just "Some guy" and not really a jesus figure. Vriska will also be there so I guess the Candy kids can have two mentors like an Angel and Devil situation </3 Vriska could convince them to take chances and risks and not to be complacent, and Karkat can talk to them so they chill out or whatever since this is an adventure that is due to cause a lot of trauma </3