There's been a few of these posted in the past and I thought I'd post one myself for reference. The values are based on my experience at high MP, primarily that I can farm MP9 fairly efficiently with 450k dps and around 450k EHP. With those values you should be able to kill elites in a timely fashion (10-20s for most). Having higher values will obviously make farming easier, so these are more like low end recommendations. I'm guessing a lot of people will recommend much higher EHP values, and I won't argue with that. My only claim is you can make it work with the values listed with the right gearing choices.
Buffed DPS and EHP
Improved Archon rune
Cold Blooded with cold damage follower is optional but helpful
Sufficient mitigation to not have problems against RD
450k dps and 450k EHP for MP9 farming
DPS scales directly with mob health
EHP scales directly with mob damage
solo farming both elites and trash mobs
Minimum Recommended DPS and EHP for each MP
My personal preference for EHP gearing is to get about as much buffed mitigation and LS to break even against RD mobs, then have a couple Physical resist pieces to push me even further over so I can gain life against them. If you just break even against RD you can still die to them because of their base attacks or if they have extra annoying affixes like plague, desecrator, or electrified (I especially am starting to hate electrified).
I have no similar table for those who don't use a LS weapon or who run LS weapon but no blood magic. I have always ran with a LS weapon because I find it makes higher MP tons easier
Feel free to post if you disagree, but please state why so we can get a good discussion going. Posting in agreement is also fine.