Extra Functions/Variables in "Session Filters"

Can we please expose more functions and or Variables to the Session Filter section of the Session Group Editor?

Can I suggest (specifically for SAML users) the following Variables:

$EMAIL

$UPN

Can I also suggest the following FUNCTIONS to be added:

Mid(string, start, [ length ])

InStr([ start ], string1, string2, [ compare ])

Replace(expression, find, replace, [ start, [ count, [ compare ]]])

A good example of how this could be used is a Session Filter called:

"Where am I logged In currently":

GuestLoggedOnUserName = $EMAIL

There are so many BASIC functions missing from this feature, and it would be great to finally be able to use it as powerful as it is.