Based on Karkat’s recent speech and past actions the Blood aspect is definitely about unity and friendship and shit like that.  

The dreambubbles are referred to as an afterlife by trolls on many occasions

?GG: it hopped over to me and i picked it up
?GG: but then, just like that…

?GG: it died

And then she talks about Jadebot and Echidna’s request. No reasoning provided for the frog’s death.

They’re around, rap battle bots do their own thing

Yep, post-retcon Gamzee never got to antagonize the Alpha kids and create their sprites

John was actually the first human she talked to

Yes, but we don’t know where it came from or why/how it died.  It just appeared and keeled over in front of tiny Jade.

Jane was often not allowed to leave due to multiple assassination attempts. And none of the the Beta kids ever mentioned school or other friends.

Personally, I’d like the Warhammer of Zillyhoo’s timeline to become finished because right now we’re missing a chunk.

Also what has up with the white beta-kid-colored eyed lsat frog that Jade needed for frog breeding.

The Sprite, never existed.

The Ship, is still around probably.