I tried a "new" case recently (a Corsair 275Q). Ended up ripping apart the front panel so I could prop some 5.25 devices in, then went back to a Cooler Master HAF XB, which so far is the best combination of size and utility I've seen. I'm afraid that's likely discontinued too.
The things I'm surprised you don't see more of:
* "horizontal mainboard" form factors like the HAF XB. With the enthusiast video cards that weigh like 2kg and literally sag when hung from a normal tower case, you'd think people would prefer the stability. Thermaltake offers a few, unless they're already discontinued, but aside from that, most horizontal cases are '90s retreads, rackmounts, or expensive boutique custom jobs from firms like Mountain Mods.
* Cases with (at least) a single vestigal 5.25 drive bay. There's a market for it, even if it's the "I need an optical drive ONCE to read my 2006 backup CD-R/rip my parents' old CDs" crowd, but also "this apartment isn't big enough for a PC and a seperate media stack, so I use it to watch DVDs." You see more of this on office PCs, the Optiplex style cases usually have one or two. But the alternative of external optical drives are a mess. What seems to be on the market is no-name lowest-bid stuff now. I bought one, and found that it was clearly a salvaged drive from an old HP laptop inside (complete with FRU stickers) that didn't match the specs advertised.
Given the recent trend of people installing mobile phones or little HDMI displays in their cases for status monitoring, that could have been another space for 5.25 bays-- a monitor designed to fit the mount would look clean and be adaptable to many different cases.