Mass-effect – How does the Venom Gauntlet poison damage work

There are definite synergies between various classes and certain weapon types. First of all, many powers and abilities only work with specific weapons, or give special bonuses when used with specific weapons. For instance, Vanguards have access to a number of bonuses to Shotgun damage, and Soldiers have access to several Assault Rifle upgrades. Infiltrators have access to lots of Sniper Rifle synergies.

Additionally, only Soldiers and Infiltrators experience the 'time dilation' effect when looking down the scope of a Sniper Rifle - this is invaluable for setting up headshots.

Finally, different classes have different weight allowances. Because some weapon types - notably Assault Rifles and Sniper Rifles - are much heavier than others, trying to carry one with a class with a low weight capacity (like an Adept) will result in a large penalty to your power recharge times. This is an important tradeoff, since these classes essentially live and die by effective use of their powers.

TL;DR: While you aren't required to use certain weapon types, there are definite rewards for specializing in something suited to the combat style of your class.

What you're dealing with is basically just the fact that it's a slower payoff than a melee specialization.

Sticking with the cloaking and sniping tactics will payoff. You'll have to invest a lot into building your rifle up, but eventually most enemies will be one-shot kills unless they have multiple layers of shields.

Of course there is a lot more in the way of hybrid options in ME3 than there was in ME2 so some of it will be up to you and how you play the character.

Cloak + Shotgun = AMAZING!

Right now my load out is: Mantis V Wraith V Shuriken V

Cloak and Operational Mastery are at 6 and Fitness and Disruptor Ammo are at 5. Everything else is at 1 until I max the others out.