A bud is thinking a raider fleet. Is that feasible? What ships? and how many of each? would he need to compete against the starter boxes of other races?

I'd only get Raiders as an additional fleet, to only a few raid points. If you can field a 5 point raid fleet you can play in the average game but getting more would just be dull. There's only three Raider ships and two fighters in Sky Full of Stars. Armageddon expands them a bit, but it's still not really a front line fleet.

As for what to get, at 5 point raid I've have two Battlewagons, four Strike Carriers and a full raid point of Double-V fighters.
As LDtD said, it is best for the small scale games, Raid is really the top end as you will end up fielding only masses of the same ship types.

The fleet he has outlined will cover you for most instances, but I would consider grabbing a couple of league ships (probably Drazi - they have the raider mindset, and look cool) for 1 of the strike carriers.
Actually id forgego the Strike carriers. You get the same Delta-Vs in bigger numbers by just getting fighter wings. And the Carrier itself grants no bonus to your fleet. Actually it is slower than the fighters, only giving marginal use to its Jump point, though jumping fighters behing enemy lines would be a new one. The firepower isnt really up to anything, and i wont even talk about its survivability, should the enemy actually deign it with some attenttion.

For raiders get battlewagons, they are actually a fine ship, and look into getting either Argents Crusaders or the Ghosts of Omelos as a raider fleet, that should give you more options without havint to go too LONAW heavy, though the Ghosts give you many nice options they arent really the standard raider fleet anymore.
I'm about to start a Raiders campaign against the Vree using the Ghosts of Omelos, who I believe make the Raiders a viable, competitive fleet.