Also, I would like to know what everyone's characters would be like in a post-scratch session - namely, who the replacement player would be, personality, class, etc.
I actually have some given that a little thought for various reasons:
Alex's Post Scratch Bro would be obsessed about wood cutting. To the point of talking about it like its a Sacred art, and practicing it religiously. I imagine he'd do so in some kind of Japanese Dojo.
Mikhael's Post Scratch Father would be kinda like him. Except instead of "Attention Hogging and Egotistical", he be "Delusional and bonkers." I mean this in the sense that he believes hes an actually knight, as opposed to Mikhael who does it pretty much to look cool. I see him wearing a Helmet, Pauldrons, and a cape at all times, and he would ride around on his endless collection Stick Horses, all of which he has named.
Danielle's Post Scratch Guard would actually turn out to have always been a guy "Gu·aard". He most likely be constantly annoyed at everyone, and be very overprotective of his friends. So basically he's a version of Karkat who yells less and speaks in a slight french Accent. Also he would end up having to spend all his time correcting everyone when they say his name because of its similarity to a certain profession.
Troy's Post Scratch Father is most likely super paranoid, believing that all the undead ghosts are out to get him. Hes basically completely the polar opposite of Troy in his attitude towards new people. I imagine he runs around with in a brown overcoat with a pistol all the time.
The others I haven't actually given much thought about yet, but if people really like my meaningless opinions then I could give it a little more.