the best PVE legendary primaries are still the ones from the VoG
Vision of Confluence, Atheon Epilogue and the legend: Fatebringer

the rest are forgettable and aint worth your time

they are the awards for beating the certain levels in the Vault of Glass raid on Venus

Vault of Glass is a weekly raid. Each one of your characters can get rewards from the raid once a week (same like Crota's End raid, nightfall & weekly heroic strikes). The weekly reset is Tuesday 5pm.

Anyway check this out: http://www.bungie.net/en/profile/triumphs
Got to find those damn chests 

finish mine just need to do poe skolas

public event is available in all planet, just that the easiest one are on moon and earth. finally found all chest and got myself the triumph emblem. waiting patiently to claim mine in september

If you hv 3 character then u may collect maximum of 27 coins per week.

Yup do poe then, shd be  able to get a lot
BTW invoker , what's your psn id

Prison of elders. I just added you in psn. Got play together la

Yes, every Fri 5pm to sun 5pm.

yes, xur sells different armor and weapon every weekend. so, if u want some armor or weapon badly, make sure you dont miss it. Otherwise, u will have to wait for another round which no one knows when will it be.
if you bought the dark below and house of wolves, then we can go for crota's end, VOG and prison of elders. Add me up if u need ppl to play with. My clan is still quite active now.
if you are <32 level, rank up your vanguard points and purchase the gear from the vanguard NPC. of coz, if you do prison of elders, raid you will have better chance to get better armor. PS+ is a must for multiplayer including raid, pvp, and etc