All of Undas Homestuck works are amazing. Alternate Universe (my personal favorite of their stuff) (https://archiveofourown.org/works/22551601) is set in a world of magic, Karkats the main protagonist and narrator (though Rose also narrates where Karkat is unable). Features Black Karsol, Red Davekat, Pale Davesol, and pale Karkat/Rose (which works way better than you might think). The romance is written really well, it has June, Jade, Kanaya (rosemary is in the background), a really cool library, demons, witches, fae, and so on.

Thirteen and a Half Mixtapes (https://archiveofourown.org/works/5615899) Is a davekat fic featuring Dave sending Karkat on a scavenger hunt all across the town they live in. Heavily features Nepeta/Terezi.

Herding Cats (https://archiveofourown.org/works/349720) is basically ship em all, all the beta trolls get shipped, and its actually a really good read. Too many ships to really tell you, but none of them feel out of place.

Lastly I want to mention Tartarus 5 (https://archiveofourown.org/works/38229085) which is entirely original, basically all of these god tiers are doomed and have to go into a battle royal to determine which of them gets a second chance. Of course, this features some cool classpect powers, and is generally really cool with just original characters. Ongoing with semi-frequent updates.