I don't think it has to be either/or like this! You can keep the characters exactly the same and give them a different name and a different hair colour and suddenly it's "based off of Joe" instead of "literally a cartoon version of Joe."
I ran a journal comic for four years. I also based 2 of the main characters of my fantasy comic off of friends of mine! Those things were very different experiences.
From my experience, I highly recommend pulling inspiration from real people when making characters, whether blatantly or secretly, because it brings a different voice to your characters. But I do not recommend putting a real person wholesale into a long-running story, unless it's just a thing you're doing for fun.
Some difficult things that can happen when characters are literally you & your friends -- we'll call them Joe and Sam:
- You write Joe-character doing something that Joe doesn't like. You didn't mean to insult him but somehow it did. The comic is harder to write, since you feel like you can't ever make his character look bad.
- You and Joe have a falling out. He does something crappy and you never quite make up. You feel weird writing his character now.
- Joe and Sam get into a fight and stop speaking to each other. You're still friends with both of them and have no idea how to handle this in the comic.
- You and Sam stop talking as much. You want to take her character in a different direction but are afraid she won't like it. The comic gets harder to write since you feel confined.
- Readers don't like the Joe character. Joe gets frustrated and hurt by the reader response. You feel kind of guilty and want to defend him, but also don't want to be defensive about your comic.
- Readers ship your character and Joe's character and draw them kissing. This makes Joe PROFOUNDLY uncomfortable. You've asked them to stop but the whole thing feels awkward now.
- Sam becomes uncomfortable half-way through when [any of the above] happens to her and asks you to remove her likeness and name from your comic.
All of these are okay if you can just quit the comic, because it's just for fun. But it'd make it difficult if this is a story you really wanted to tell!
The thing I learned from doing a journal comic is that, while I'd built up the ability to be okay with twenty or so well-meaning people suggesting how I should live my life three times a week, it was much harder for my friends not to feel defensive in times when my readers had opinions on things they were doing.
It's also really tough to write a character who can't ever look bad in a story. And it's an even trickier thing to write a real person's real flaws in a way that they're okay with.
So TL;DR: I think it's fine and can be a lot of fun to write characters who are based HEAVILY on you or your friends, and I've done it myself! But I'd advise against making them Actually Your Friends; drawing the distinction that your friends inspired these characters protects both you AND your friends from some tough possibilities.
