Zunimassa's set gives 55 AR
IK set gives 60 AR (which is ridiculous because barbs get 300 AR with 3 pieces of the set without having to roll any random affixes, which becomes 450 AR with warcry which also adds a generous 20% armor bonus)
Nats set gives 7 crits
Tals set gives +3% to all damage, which is kind of skimpy but it's still much better than:
Inna's set -- +0.33 Spirit regeneration
Seriously, 0.33 spirit regen isn't even remotely noticeable. It's actually rather insulting, especially paired with the measely +10 life per spirit spent from the 4-piece bonus, which I think should be changed to one of the following as well, personally.
Here are some suggestions on what it really SHOULD be, counting down in my opinionated order of importance:
10. +0.15 attacks per second. Not many modifier like it out there, and this would be very nice for making Inna's staff more viable for use.
9. +250 life on hit and +1.5% life leech. All monks can use both of these. Monks with high-hitting 2-handers and dual wields will appreciate the leech, and monks with faster, lower damage weapons or monks using shields will find the LoH valuable.
8. +3 spirit regen. This is less thrilling, but it would open up a lot of new builds and it's the same bonus but isn't pathetic.
7. +1000 armor. All monks benefit from more armor, and the set pieces can only roll very mediocre amounts of armor as it is.
6. 30 Life per spirit spent. This one would be nice and could help a lot of monks who are using transcendence to free up a passive slot, improving build diversity.
5. +8% critical hit chance. Monks currently don't get anything that increases their crit chance other than gear rolls, and they have a lot of spells that react differently to critical hits. This pales in comparison to the other suggestions, however, because it makes Nat's set and Inna's set too similar.
4. +20% critical hit damage and +8% attack speed. Very useful attributes that currently aren't any class set bonus.
3. +80 to all resistances. the set currently gives 0 base resistances and that's appauling for a class like the monk, having to roll random affixes makes the gear extremely expensive just to be useable, and some of the pieces become unuseable if they do roll thoe resistances
2. +10% to armor and resistances. This is one I would very much like to see, I'm just not sure how practical that kind of thing is to actually add onto gear.
1. 10% cooldown reduction and +5% attack speed. I like this one the best because the monk feels very slow to play with. This seems like it would be better suited for the 4piece bonus, however, and the 3-piece bonus would be better reserved for something defensive like #2.