agreed on MONITOR command, i rather just use INFO however on our deployment, top keys and commands are usually the most important information i'm looking for and with 2.4 there is currently no way.
When full monitoring is needed (like for the top keys) but still the analysis must be run continuously on a production instance, maybe in the next version of MONITOR (already planned) we could say to it "give me N items and return back in normal mode", or a similar thing but with time (for instance 1 millisecond), so that it is possible to perform some kind of polling that has no serious impacts on the server. Well I'll think about this when I'll reimplement monitoring :)
In redislive, the monitoring duration is configurable via command line argument, the idea is to schedule it as a cron job and monitor every 6 hrs for 1-2 minutes, that's enough to build the trend for analytics.