For context, I’m talking about the three craftable 476 ilvl staves from Inscription (Int+Spirit, Int+Hit and Agility).
In the original MoP system, the only difference between an Heirloom and these craftable staves (+ Archaeology items) was their quality/color - Heirloom-quality stuff was also BoA and you had to keep track on which character it was on instead of learning it once and being able to create new versions on new characters. The Collections tab as we got it mid-Wrath Classic was originally added in WoD’s 6.1.0 patch.
I think this would be a sensible QoL change that wouldn’t take away from anything since in the current system you still need to only craft one to be able to use it on multiple characters, you just have to go through the hassle of mailing it between swapping characters. I briefly mentioned Archaeology items, and I think that they should get the same treatment. You discover Zin’rokh once? Congrats, you can make it on any future character instead of having to keep track of it in the bags of your army of alts.
The original BoA system made sense in a world where we didn’t have the Collections tab, but I believe the usage of the Collections tab should be expanded.