Campbell
Relaxed Intensity
All you have to do is consider the tight theme or niche as the “client” and you can dispense with this degree of semantic nitpickery.
I’m not convinced bespoke is necessarily the best term, but it withstands your complaint just fine and will do until some better term evolves.
What purpose does bespoke serve other than to essentialize all roleplaying games, to treat some games as more specialized forms of other games?
Right now, my Saturday group has just finished the first season (3 month run) of our L5R game. We're going to do a sort of 7th Sea. After that it will be my turn in the GM's chair. One of the games I'm considering is the Dishonored 2d20 game which shares a fair deal of conceptual space with Blades in the Dark (players play a group of criminals in a pseudo-Victorian industrial wasteland with all sorts of occult stuff going on). I expect the experience to be wholly unlike playing / running Blades in the Dark. Play is going to be a lot more zoomed in, a lot more focused given to individual social interactions and day in the life type stuff. The setting is also a lot more locked in and specific. While there will be factions the individual character relationships with individual NPCs will likely be primary. These two games who share a remarkable amount of conceptual space are not even close to being substitutes for one another.