Actually, I think he said they'd look at a list of candidates and narrow it down to 2 or 3 guys and bring them to Ralph. So, the list would appear to be longer than 3 guys.
However, your other point seems like a dead on accurate assessment. The longer they go without naming a HC, the deeper on the list they're going. Should be interesting to watch it develop.
I'm not sure how much legitimacy he'll bring in comparison to a name guy like Holmgren. But, I haven't heard/read one negative word about him in regards to his football knowledge or capabilities in evaluating players. The legitimacy could certainly be a nonissue if a guy like Cowher is hired as the HC, though.
If you listen to the PC, they clearly tried to temper all the talk of a big name HC by saying sometimes you get a guy like Sean Peyton. So, although they may be going after Cowher bigtime, it doesn't seem like a done deal to me at all.