Ascendant Nomad just put out a vid on the best pulses. I definitely recommend checking it out as pulses are his thing.

My personal favorites are:

Piece of Mind- craftable for a God Roll and has lots of zoom, giving some of the best range of 540s.

Third Axiom- 390s are usually considered undertuned, but Axiom is one of the better ones- good stats, feels great to use and if you can get a good perk roll, it actually can slap pretty hard in 6s due to its forgiveness and ease of use. My roll has Chambered, Ricochet, Killing Wind and Rampage and I love it.

Insidious- 4 burst aggressive. Craftable with a couple good rolls that work for both PvE and PvP.

Outbreak Perfected- Exotic, so might be harder to get, but it's a good 450 with a perk that spreads damage to other opponents when they are nearby and that damage is increased when Radiant.