Dragon and Druid sound like viable options.

Dungeon architecture? What's that?

Looks to have been a joke about the alphabetical naming: Alchemist, Battlemage, Celestial .. Dungeon

(There’s no name decided yet for the fourth in the series.)

There is, it's Druid. Intel announced the first four codenames in 2021.

> [...] first generation, based on the Xe HPG microarchitecture, codenamed Alchemist (formerly known as DG2). Intel also revealed the code names of future generations under the Arc brand: Battlemage, Celestial and Druid.

https://www.intel.com/content/www/us/en/newsroom/news/introd...

C should have been Cleric, and I don't know about E (Eldritch Knight?!), but if F ain't Fighter I'm going to be disappointed.

E could be evoker, enchanter, or exorcist. F could be Firedancer, but will probably be fighter :)