Pretty tough question. I guess it depends how much you weight certain skills (making long thin cuts) vs. other skills (making jump shots).
I mean, we can all agree a game that tests shotmaking is useful, but do you rank a game that demands better shotmaking (like 9b/10b) higher than a game that demands breaking up clusters and moving through traffic (8b)?
I voted 14.1 reluctantly. Yes, there are far fewer banks than 1p, and far fewer kicks than rotation-type games. And there's no testing of your jumping skills, which I'm sure some of you will say shouldn't even be part of the equation. But I think pool is ultimately about pocketing balls, playing shape, planning, breaking clusters, and making pressure shots. You can do all of those things in any of these games but in straight pool, you pocket more balls (and have to play more shape) than any other game. You have to break more clusters too, though 1P features a lot of bunting. And you actually see a lot of tough shots in straight pool. The rack is wide open and they can shoot any ball in any pocket. You just happen to have fallen where nothing easy is available. Do you sell out on a false safety, knowing they'll probably get a look at SOMEthing? Nope, you try that tough backwards 7 foot cut or whatever. Or, god forbid, you bank one. Almost all of those weird shots come up eventually.
I want to give 1p the credit it's due, but I feel the game focuses less on shotmaking than other games. Yeah you see some fantastic shots during an 8 and out runout, but mostly you see guys maneuvering and 10 safes per actual ball shot. More common than the spectacular runout with lots of weird thin cuts and precision shape is the regular joe who makes four open balls, ducks, plays safeties and knocks out a more shots, traps the other guy... eventually gets a shot at another open ball or two, and finally gets out.