To me, the Vanguard experience on multiplayer is charging blindy into a horde of enemies, and then praying that a teammate gets to you in time once you've run out of medigel.
Krogan Battlemaster on Gold, Katana X with Shredder & Bayonet, Rage specced out for melee, Queen's Don't Stop Me Now blasting out of my computer, melee only. Until turrets show up. But Vanguard does kick ass!
A Krogan biotic charging.
I've seen Vanguards walk into fights carrying assault rifles. ASSAULT RIFLES.
For shame.
Until an Atlas or a Turret show up.