A little over a week ago we upgraded from AWS's standard EBS storage to the new General Purpose SSD backed volumes and the speedup has been tremendous. A set of queries that was taking ~28 minutes is down to a little more than ~2.5 minutes, which shifts the feed fetch bottleneck to be mostly the download times.
In addition to speeding up the background tasks like fetching feeds, scoring, and grouping, you should also see an improvement in completing requests made in your browser. FeedsAnywhere already makes judicious use of prefetching your next page, as well as keeping previous pages in cache in case you need to go back, but activities such as viewing similar items or waiting for unread counts to update now have a shorter delay.