Maybe new CU update are better to bring up to date a new installation, but in general they install longer (i'm seeing this as Windows 2008 servers updating twice as fast by pulling 8-10 separate updates, than Windows 2008 R2/2012 updating with just a few CU updates). When all PCs in the network are patched and up to date, installing CU updates is longer downtime. I'm looking forward what will going to Express updates bring to the table (as described in other blog post).
As for this issue. We have been installing critical updates along with security for 15+ years. I guess it was worth it :) They are called critical for a reason. Although, i would vote to get rid of one category and just move all important update to security, so it would be easier to triage new updates every month (in WSUS one has to make a combined view or go twice through every category).