"After 25 years of PPL'ing and with a BCPL in my back pocket, I've taken the first step down the road, by going for the Class Rating Instructor."
Excellent! Good for you! The CRI is an extremely worthwhile Rating to include on your licence if you are in a club environment. To my mind you are using it for precisely the correct purpose; I consider that all club checkouts should be done by authorised instructors.
A club I know uses so-called 'check pilots' who do not hold any form of instructional rating. Not only do these people claim the time as PIC, but also make the person being 'checked' pay for the privilege....
I suspect the low number of CRIs is because hardly anyone knows of the Rating or its privileges. The PFA coaches all became CRIs under 'grandfather rights'; however, many didn't know they had to revalidate (which is very simple) and, as a result, had to renew at their own expense. Sympathy...? Nah!