I am a monk setbuilder for the Institute of Heroes and build monk sets every day, ranging in budget from 500m-10b, so I am confident answering your questions and concerns.
I always put gearchecks into two sections, comments and suggestions, so here goes.
You have a decent amount of EHP (and depend highly on the life gem in helm), however you have no sustain - which comes from either high LoH or life steal. Breakpoint for LS to become more efficient than LoH is around 90k dps, so LS is the way to go for you.
Your hp pool is way way low, even with the life gem in helm, aim for 40k without life gem - will maybe cost dps, but worth it in the long run
d3rawr has your current res at 570, which is too low at your dps level, I would personally aim for 680
Building a monk is all about balance between EHP and dps, you seem to have overfocused a bit on dps, we have a saying: "Dead monks do no dps"
This is a matter of taste, but I really dont like EF on monks, unless running slow MH and put EF in OH, and even then, a socket + LS WKL outperforms it. Plus side is that a WKL is a much cheaper option, but provides less sheet dps, but a lot more ingame dps
Suggestions Disclaimer: It has been a while since I built a monk on US, so I dont know the current state of the AH, so will be going with EU prices
Loose the vit on nats boots, go dual res (125+ total) (10m)
Go double vit on innas pants 90+dex/160+ vit/9% (if affordable) (40-60m)
Get high res on vile wards, look for 190+ dex/80+ vit/125+ total res and high armor (10-30m)
Change innas helm to 180+dex/180+vit/6cc/50 chosen res (10-40m)
Go higher res on WH, look for 70+ dex/70+ vit/50+ res and as much dps as you can afford (10-60m)
While your nats ring has crit, it has no res, at your budget I always recommend going high avg. dam (52+), 45+ res and 9% (10-30m) - add crit if you can afford it
Upgrade bracers, go for 120+ dex/70+ vit/120 total res/5+ cc (10-40m)
MH: Look for 1000+ dps, 100+ dex, socket, CD and 2.6+ LS (30-120m)
OH: Look for a WKL with socket+LS, preferably with 340+ min damage roll, and dont drop +lightning skills below 22% (important!!!!) (30-50m)
Instead of rare ring, if the res allows it, buy a 5-6% AS unity with high avg. dam (30-60m)
In general, you will need to upgrade one item at a time, always do the res upgrades first, so you know when and if you can drop res on other items. This will drop your sheet dps, especially if you go WKL, but will be more ingame dps and surviveability.
If after doing upgrades, you hp pool allows for it, upgrade amulet to high avg. dam (35+), 8+cc, 60+ CD, and 100+ dex - look to see if you can get res, vit or armor here as well. WH is a good place to get an armor roll as well.
For now, the most important for you is getting the sustain from LS, so look at weapons first.
Hope this helped, if not, come over to www.institutetofheroes.com or twitch.com/bealzibub, and tap in to some of the awesome monk resources we have there.
Did you simulate that WKL, and check your actual ingame dps output? Your findings pretty much contradict all the simulations I did, and what the findings of top monks say. Remember, it is not sheet dps, sheet dps != ingame dps.
When I build a 500m set, you normally end up at 130+k dps with 23+% WKL, that equals 159,9k ingame dps (with cyclone/thunderclap build), BUT that is with 40k hp, 680+ res and 4700+ armor and dual LS. So there you see the effect of a WKL directly.
If you do infact have LS weapons, they are not on your profile, and thus is not part of the gearcheck.
I stand by everything I wrote, you should basically never die on MP7 - cruise through MP8 - and be able to do MP10. That is what a 500m set normally gets you.
As for your build, I recommend dropping resolving, get combination strike, and drop serenity and to way of hundred fists - blazing wrath.
The math is pretty simple, Way of Hundred fists gives you 15% attack speed, and combination strike gives you a flat 16% dps increase. This is all achieved when you use FoT - Thunderclap and Way of Hundred Fists once every 3s.
You should not need serenity if the monk is build with proper EHP, use blinding flash with dual LS instead, provides more surviveability due to the massive dps increase from blinding flash.
I just simulated a 943 dps / 5% / 24% lightning / socket WKL on your gear, these are the results:
Effective DPS with your current weapon setup:
FoT: 360313 dps
Sweeping wind: 239860 dps
Total: 600173 dps
Effective dps with EF + WKL:
FoT: 425218 dps
Sweeping wind: 283060 dps
Total: 708278 dps
These two skills comprises over 90% of your dps, since mantra just applies a static buff to all dps skills, which means that with a non-CD WKL, which can still have LS on top, you gain 108k effective dps.
You might say, but that is only FoT and Sweeping wind? But they make up 90% of your dps, so lets just go ahead and subtract 10%, that is still 97.2k dps gained when using WKL.
The whole serenity discussion I dont wanna get into, but using it you loose 15% AS and 16% flat dps increase, so it is suboptimal.
Edit: In your previous calculations, did you simulate it vs. the LS EF you talked about, otherwise it is deeply flawed because you compare a LS weapon to a non-LS weapon?
You asked for advice, I gave it, I cannot make the decisions for you, you asked for math to back it up, and I provided it. You might not agree with what I have adviced you to do, but it is experience I built over countless of hours playing monk as well as building well over 50 sets.