Best feed aggregation module to build a community blog aggregator

I'm building a community blog aggregator using Drupal and have tried out several feed aggregation modules. May be I'm missing the logic of doing this but none of the modules seem to fit my purpose. What I'd want to do is have "Most recent posts", "Most voted posts" etc (i.e. feed items coming not from a single feed, but from multiple feeds and then have them mixed according to the criteria I need). On the front page, I'd want to list the posts of the listed blogs as an when they are published, ordered by the time of their posting. As far as I've tried out, modules like Aggregation, FeedAPI all allow us to publish external feeds coming from a single source, but doesn't allow us to jumble feed items from multiple feeds.

How can I achieve this? I'm relatively new to Drupal but have searched and experimented using examples available on the web. Still with little success. May be it's more of a coding issue rather than a problem with the available modules. If so, kindly point me to someplace where these were discussed before.

In addition, I'd want to enable the users of the website to recommend feeds of the blogs they may think is useful for others as well. This means that the number of feeds that this site will aggregate could reach hundreds or even thousands if it becomes successful. What is the best module I can use in terms of performance in parsing a large number of feeds.

Thanks in advance to anyone that pours their suggestions.