Build/design an RSS feed archive system in PHP

We want to build a simple RSS feed archive system that works a bit like [login to view URL] (but can be crawled by Google). - we need to find an initial 30,000 RSS feeds - we need to download the 30,000 feeds once per day (cron job) - we need to deal with timeouts and feeds that are not updated properly - each feed gets one nice URL from title i.e. [login to view URL] - we need to manage feed updates/ growth over many years with a URL structure that can be followed by Google - some feeds contain just headlines/ excerpts or full text (needs to look nice irrespective) - we do not need individual 'pages' per feed item - we need to keep track of updates - we need to be able to create a sitemap and some basic 'category' - all feed content MUST be stored on S3 (S3 structure should resemble URl structure for easy retrieval) - we set proper cache headers (one day for feed URL page, much longer time for any feed content from the past) - minimal database used allowed (ideally none) - minimal CPU usage for small EC2 instance allowed - basic web design needed