Hmm I can't think of many off the top of my head.

There's

nostr:nprofile1qqsp4a2f2kfkh6qyl9gpqer75kk6t3mz0mwlqu6207qnhwswx8hdjcqpz4mhxue69uhhyetvv9ujuerpd46hxtnfduhsz8thwden5te0dehhxarj9e3xjarrda5kuetj9eek7cmfv9kz7qg4waehxw309aex2mrp0yhxummnw3ezucn89unqla3n - rugmaker

nostr:nprofile1qqsy6j4hxl30hdd0pl2epd9harr0uakn5q4f0y000ldv7cqlneg04kqpz4mhxue69uhhyetvv9ujuerpd46hxtnfduhsz8thwden5te0dehhxarj9e3hjurgv4e8qatwdvh8gmmyv9uj7qghwaehxw309ahx7um5wghxy6t5wp6ku6ewvekj7su0fdq - cassette andusic experiments.

There are some people who make alts to be topic-specofic, like one you already mentioned.

nostr:nprofile1qqsx7ld4tgxe92jj6tan75krnseqkp9a9jktl8a5r469zf89npwckfgprdmhxue69uhhw6r9v96zu6rpwpc8jarpwejhym3wvdhj7qgnwaehxw309amk7apww468smewdahx2tcpr3mhxue69uhhyetvv9ujumn0wd68yetvd96x2uewdaexwtcfdjf3n - gaming

I would look up nos social's programme. They seem to focus on accounts like this nostr:nprofile1qqs8d3c64cayj8canmky0jap0c3fekjpzwsthdhx4cthd4my8c5u47spzfmhxue69uhhqatjwpkx2urpvuhx2ucpz3mhxue69uhhyetvv9ujuerpd46hxtnfduq3vamnwvaz7tmjv4kxz7fwdehhxtnnda3kjctvll3q2p (?)

I posted earlier today actually about there not being many topic-focused accounts. Nostr sort of (accidentally?) deincentivises posting like this because of the dominant bitcointwitter culture. I e seen a few promising account spring up like this, be most are demoralised by lack of engagement, community/conversation and leave.