Asset is great term that everyone seems to like using. Unfortunately it's being used differently in other place all the time. Example:
Shotgun Asset = a piece of work reused in more shots or places, like character, environment, backplate etc. can have lot's of subelements. tasks, published files, versions, etc.
Ftrack Asset = A container for version of certain type. Not the full character, but a character model for example. However this can hold multiple components in each version like Low res mesh, Hi res mesh, preview quicktime etc.
Equivalency roughly based on what they contain:
Asset = Ftrack
Asset Build = Pyblish
Version = Ftrack
Asset = Pyblish
Published File =
Ftrack Component = Pyblish
Of course this is very much an approximation, because there are big overlaps. I'm not trying to steer away from asset here, but merely trying to point out how differently it is used in many place (not to mention, that many studio have their own understanding of that asset actually is).
At the same time, changing the name from instance to something more intuitive would certainly help new people understand the system quicker.
The problem I see is that Pyblish instances can be of such massive variety, that maybe something more general than asset might work better. Even though 'asset' is still better than 'instance'.
I don't really have suggestions at this point. Just wanted to paint a full picture.