No ancient music time signatures

When editing ancient music, you're very often faced with tempus perfectum or imperfectum and with proatio major or minor.
It seems that those markings aren't more available than in previous versions, ie in the Time Signature Properties inside the staff.

Ideally, those should be selected instead of the standard fractional signature, like Common time, Cut time, Bach notations and so on.
More on this: It does not have very much to do _ with actual bar length.
For example, you can have an cut time signature with an actual bar duration of a maxima: it only signifies that the inside beat is on the half, _not that there are two halves. So you can use this same TS with 2/2, 3/2, 4/2, 5/2, etc.
It would be great to deal with this, and to show in the balloon text of the palette, the fractional value associated with this graphical sign.