My workflow has always been Workbench for front-end UI, DOpus4 for back-end file operations.
Sure, so was mine - and probably every other Amiga user's. But "frontend UI" basically means using WB as a program launcher - and for that little functionality, you had to spend way too much time finetuning it IMHO.
I'm not bashing WB btw. - back in the early nineties, all the desktops had tons of annoying quirks. It's just that WB never evolved, and we've been using it way past it's original expiry date.
I thought LeftAmiga V/B was universally recognized by Intuition?
No, it's an ASL thing, not intuition (IIRC - it's been a while). Meaning that any application not using ASL would usually not respect these shortcuts.
I guess not. What could Commodore have done here to enforce standards?
The original Kickstart didn't have any UI toolkit worth mentioning, due to lack of time and ressources, and probably Mical's lack of experience and research on the subject. Once you sold millions of machines with that version of the OS, you have a problem. Commodore would have had to come out with a UI toolkit addon ASAP. One that worked under 1.x and was free to install (or distribute with commercial applications). But that's probably asking too much, given Commodore's problems at the time, and the total lack of any UI experience - let alone research on the subject.