I see you have a great deal of choices throughout the VATUSA devision and I admire what you are trying to do and what you have done previously.
I would like to put my ARTCC out there for a choice as well. ZLC. More specifically the
SLC TRACONAs seen in the SkyVector link above, a course of flight that will introduce the following:
__A very large and stacked Class B airspace right in the middle of the TRACON.
__No Class C within the TRACON but take a trip up to KBOI and you get what you want there. (Still within the ARTCC). Two class D airports can be found in the SLC TRACON: KPVU and KOGD. There is also, merging with KOGD, a air force base class D KHIF.
__Both Large and small VFR corridors between the Class B and D airspaces.
__VFR transitions through the class B
__Restricted airspace
__Controlled and uncontrolled fields
__Terrain obstructions
__Cannot see it on a chart but ZLC ARTCC's SLC TRACON has more to offer such as a wide range of weather throughout the year and a FRIENDLY/active CAB and RADAR controller roster
A simple email to the staff concerning scheduled training dates and times could set up an opportunity for both your pilots and our controllers to improve the chances of attendance.
Regardless of your decision, I wish you the best of luck!