I fly a 2x raider, 2x gladiator, ISD-I fleet in tournaments. My raiders are:

Raider-I

Instigator

Raider-I

Assault Proton Torpedoes.

The Instigator and 2x TIE fighters is my entire anti-squadron complement, and it is very effective. Often all you need is to tie up the enemy squadrons for a turn or so, and the Instigator title makes a 49 point extremely effective squad-staller while also giving you an advantage in activation order.

I have found that my other raider is captained by a devil-may-care madman whose propensities for ramming make him an invaluable addition to the imperial fleet in disrupting enemy formations... right up until he dies. In turn 3/4, nearly every game. But man, can you screw up a conga line with a single well-placed raider. The APTs and my Screed give him a good chance to cripple the enemy as well. That's a 51 point ship capable of a surprising amount of damage output if it can get a double-arc at black range.

That said, I understand everyone else using more complicated raiders, but I tend to put my upgrades on more survivable ships. My nearly bare raiders punch far outside of their weight class just in terms of activation order and disruption.

Confusion to the enemy!