I was in high school during Vat II. I remember the changes well, and the joy of my parish priest and dear friend that he could now say Mass in English and actually understand what he was saying!  I remember how hard he worked with our church choir and with the congregation to encourage the singing. With his charisma and  encouragement, people did learn to sing out. They enthusiastically became lay readers and lay extraordinary ministers helping with communion. We had a strong and active parish council-- our pastor welcomed it.

I think the changes you witnessed, the change in the number of vocations, the drop-off in attendance, happened to ALL mainstream churches, not just the RC, so can't be blamed on V2.  It was a period of societal change in all aspects. 

I admire the Unitarian/Universalists--they are very forward thinking and active for social justice.  They do a good job of living the Gospel--even without belief in Jesus!  But don't you miss him?