The girl who speaks in tongues and the boy who speaks in signs. Both appear only to be truly understood in their speech by one person, an ex-matesprite.  Both make other uneasy in their presence.  

I can totally see them hangin’ out.

Yeah, Caliborn said he was going to steal his last name. Caliborn also wanted to groom Jake into a worthy adversary. 

That’s not canon. It’s been in the fandom for years though and I’m not sure exactly how it got started, my best guess would be from a fancomic.

It’s unknown why he has more

no

None of the currently alive trolls that haven’t ascended can ascend through any means that have been stated in canon.

I’m no English major so this isn’t a perfect analysis but,

It would be lazy because there’s been no build up to it. Creating a new Matriorb has been a thing for years and Roxy was forced into the role of attempting to create it by the Condesce, and then chose to continue to try to make it of her own free will.  Jade saving the planets was also an established plot point before hand as Echidna’s request was for Jade to do so. John’s retcon was kind of lazy writing but due to Homestuck being a webcomic Hussie was able to pull that off in part to the nature of the story.  This of course is only my opinion and you are free to yours but I just don’t think it would be strong for the story if Roxy just up and made the trolls’ slabs.

He was killed by the Vast Glub

No.

She has not ascended