Most MEP items you can have "bottom elevation" or "offset" as a parameter you can tag. Revit works REALLY well to RL's.
Can we PLEASE, PLEASE have labels where we can tag the height of equipment based on the OVERALL RL not relative to it's specific level.
This would be an absolute game changer to all MEP Trades and I suspect EVERYBODY.
As an example You may have 3 levels passing through an atrium, let's say L1,L2,L3. L1 FFL is 12500.
If I draw a duct above L3 in the atrium it will automatically Assign to Level 3 BUT have the offset of the height based on the LEVEL 3. i.e it might say offset +300. In this instance having a tag that says (for example) RL19600 can keep me having the duct assigned to the LEVEL but allow the reader to see where it was exactly as designed. Straight away I know it's 7100 from the Level 1 FFL.
Levels are arbitrary and don't work for different people. i.e Arch might want to know FFL, structure want to know SS. The only consistancy across everything is Overall RL! Works every time for every person.