There are a number of them i would like to play with, I believe from reading the FR that our ecus are much more configurable then most of us know.  Things like mono exh path/ dual bank control and wideband may be possible if I am reading correctly.  My searching and reading and comparing bins has turned up nothing with regards to editing these.

a few i am interested in currently:
SY STERVK PROKON EIN system constant condition: stereo exhaust system upstream of cat
SY STETLR PROKON EIN System constant condition continuous Lambda control present
SY_NWS PROKONAL A System constant cam timing: no, 2-pt. or continuous
SY_ZYLZA PROKONAL A System constant number of cylinders (what if we could retune me7.5 ecus to be 2.7t compatible, all the hard maps would cross over)

plus many more...

Well bummer.

They are compile time variables.
The compiler uses them to decide what sections of code to include...

The first 3 things you mentioned though are easy to work around :-)

This would be very interesting. I wonder who we could bribe to get a pre-compiled program ha.

Emulated data from aftermarket widebands or direct feed with code changes.  No one has ported over me7.5 to my knowledge though.