Not sure why the profile doesn't show up in both ACR & Lightroom when properly in the User level folder...it should. Also note that the reason why the User level folder and not the ProgramData folder is that only admin level users can write to the ProgramData folder. The User level folder is the suggested folder because most any user level can write to their User folder.
As far as the relative sizes, from DNG Profile Editor and the Adobe created ones, DNG-PE is writing simplified profiles while the Adobe vender profiles are highly tuned and adjusted. I suspect it makes them bigger...
Just a note, you did quit and then restart both Photoshop _AND_ Bridge after writing out the DNG profiles to your User level folder, correct? I ask because some people have Bridge running without realizing it's running. Pretty sure the ACR connection requires both apps be quit and restarted (you shouldn't have to reboot the computer though).
Your reminder about both Photoshop (main) and Bridge needing to be shut down for changes to take effect reminded me that I had Bridge set to "auto-start at log-in". So I checked and it was still running (shown with the other hidden icons). When I "shut it down" from the UI I had thought it was fully terminated. So I completely shut Bridge down, restarted, and the new profile now appears.
Thanks for the reminder/pointer in the right direction.
That "Autostart at log-in" is always causing problems.
It's more trouble than it's worth.