Where are the Second Generation RSS Readers?

I’m subscribed to a lot of RSS and Atom feeds. I’ve tried online readers but I never found any that could match the user experience of SharpReader so I stuck with it on the desktop. But now I’m starting to want some functionality that none of the readers I’ve looked at seem to include.

Firstly the easy stuff, when was the last article posted on a blog? When was the last time I clicked through it? (I typically double click everything I want to read so it opens in a new FireFox tab. I then work my way through them.) How many posts have been made in the last N months? And, it’s a little different to the other requests, I also want it to try and open posts through Google Cache or the Coral network if they’ve gone away or the remote site is down.

Now we get to the more… odd stuff. I want to know how long, in total, I had the last twenty posts in the current feed open. This’ll help me remove sites that I delete items from with just a glance at the post title. When was the last time I received a successful HTTP response code? (I recently did a clean out of my feed list and removed anything that 500 or 404’d at midnight, every night, for five days). I can gather some of these by working through the application logs but I’d like a nice, GUI, way of seeing it.

My time is one of the most valuable things I can give a site (Amazon and Play already own my bank accounts ;)) so where are the tools to help me spend it wisely?