Blessed Increases the effect so id assume Quick Recovery would as well. I do not think either leeching strikes or briarheats self heal can critical. So increasing critical healing will not be worth unless you plan on using it for vigor/rally heals. Since your going to have high critical chance anyways, running the thief mundus with the combo your talking about might be worth it for more vigor/rally heal criticals and a bigger chance to proc briarheart. Its also important to note, there is a slight cooldown/delay with briarheart. It does not proc off every single critical.

The healing from briarheart is very underwhelming and i would not build for that specifically and just use it for the damage. Its like a small bonus. I myself have experimented with briarheart in pvp with caltrops and a critical chance heavy setup and it did not work out that well.

Stamina builds in general are pretty underwhelming in my opinion also and i plan on taking a break from Eso until i see some of the stamina changes coming from DB DLC. Magicka Detonation has become the meta for pvp and its not fun to counter since Leki's Focus is counter productive for a stamina builds vigor heals. So in the mean time im going to wait for the pts patch notes till i jump back on eso and avoid the trash we see in pvp atm.

Overwatch open beta is coming out soon and Heros of the Storm did get some nice balance changes. These 2 games will take my interest until the DB DLC arrives. Hopefully i answered your question.

its important to note, leeching strikes reduces your damage by 20%. So its pretty counter productive to use that for sustain with so many damage increases set wise.

briarhearts damage is worth it if you use caltrops and play in/against large groups in keep battles. The damage bonus is always up but like i said the healing from briarheart is eh.