Personally speaking, I find the rating system quite basic, and kind of misleading, in particular the Alpha portion, which is almost meaninless.
A- In the NHL, nobody gets A
B - The guys has one foot in the door, will be off the rankings very soon
C - The big bucket where 90% of players go
D - Bust potential is big.
E - E? No such thing!
Most guys start as a C, and graduate as a C. So what does it really mean? It tells me he still has a chance, somewhere between, cold day in heck, and pretty good actually!
IMO the rating needs to be expanded quite a bit, and estimate how close a guy is to the NHL.
I.E.
1st round picks get a B-C type rating
7th round picks get a E-F type rating
As players develop, F-E-D-C-B giving an indication that they are not only a prospect, but one that is in fact passing other guys drafted above him
If a guy looks like a Bust, B-C-D-E-F progression should be noted.
Example Jim O'Brien (late first rounder from Sens)
First rank C (just drafted
2nd C (Meh first year)
3rd D (Meh 2nd year, others passing him by)
4th D
5th E (Sens told him to pick up or pack up, he responded)
6th B (sees NHL time as a grinder)