Hmm, I was going to add a super fancy design to beachfront.digital when I launch V2 but I do like how quick the sites you've listed load. In any event, this will force me to be more creative in how I satisfy my design side.
I too like using non-bloated sites. I'm going to have to reexamine Pinboard as well as check out MetaFilter. I'm still open to finding more sites like these if anyone knows any. Perhaps that could be a site too (if anyone's looking for a project); a site that catalogs other non-bloated sites, and/or sites that use membership fees rather than advertising.