Create segments using calculated metrics

[#1]

Description - Ability to create segment based on calculated metrics

Why is this feature important to you -  Sometimes a calculated metrics need to be used to get a more accurate segment

How would you like the feature to work - In my case, I created a metrics of revenue with tax, which added 2 existing metrics of revenue and tax.  I then would like to create a segment of visits that meet a threshold of the calculated metrics.

Current Behaviour - Calculated metrics cannot be used in segment creation.

[#2]

This is a great idea. Somewhat related, it would be great if we could apply attribution criteria to segments as well. I'm attempting to create sequential segments using within time frame criteria, but it doesn't seem to be giving me what I would like. A much simpler option would be much appreciated.