Robin: Let me start over. Imagine Jane. Jane is new to ancestry.com. She knows her ancestors lived in Amsterdam, NY. She goes to the card catalog and plugs in Amsterdam, NY. She'll get a "hit" but she will miss a 90-year span of directories. They won't come up.
How will Jane know they exist?
I'm not suggesting this improvement for myself or for you (we don't have problems with this) I'm suggesting this for Jane.
Making the card catalog more comprehensive won't make it harder to find regional collections. It's not "either-or" it's "and." You can have cities AND counties AND states AND regions AND national entries.
You wouldn't catalog the census because that includes everything by default. You would include databases that are "partial" (such as the US directories database) so users do not have to go through them manually to see what's there.
It wouldn't be a problem if the character-recognition worked perfectly, but that's not the case. I'm sure future technology will change that.
I think I'm looking at this differently since I used to work in a library. I KNOW how to use the system, but I'm envisioning the patrons who don't. How do we make it easier for them? Again, how will Jane know there are dozens of resources for her? Wouldn't it be nice and simpler for her if they popped up in the card catalog?