Forum:ME2: Vanguard strategy and build advice?

Hi all, I'm looking for advice about Vanguard builds and strategies.

I'm having a tough enough time dealing with the close-range stuff that the Vanguard gameplay gets me into; it seems too easy for a multiple-opponent situation to just get my character shot at from all sides and quickly annihilated unless I have fortunately-timed cooldowns on the squadmates to disable the other enemies. What would I do to better "get" how to play the Vanguard effectively? All too often I end up playing instead in a style that seems better suited to Engineers or Sentinels, relying on the SMG as the primary weapon from cover to strip off protections (especially against shielded enemies), as it seems that playing the classic "Vanguard strategy" gets me a Game Over far too frequently. (Yes, shooting-games never were my area of expertise, and it shows.)

Currently my character's build is as follows (it's not a high-level character yet):

Weapons: Eviscerator Shotgun, Tempest SMG (haven't yet got the Locust), Carnifex Hand Cannon, Collector Particle Beam

Powers:
 * Incendiary Ammo 4 (Inferno Ammo)
 * Cryo Ammo 0
 * Charge 4 (Heavy Charge)
 * Shockwave 0
 * Pull 0
 * Assault Mastery 3
 * Bonus: Flashbang Grenade 1 (used to have Warp Ammo)

I am currently playing on Normal, but I'd be interested in builds and tactics suitable for higher difficulties as well.

Is this a recommendable build so far? What changes would be good ideas? I've been trying to experiment with bonus powers, but the universal cooldown interferes with the use of non-Ammo powers (e.g. Barrier, Reave, etc.).

Any advice would be welcomed.