It's very easy to say that this squadron is just the Imperial variant of the HWK-290. Possessing the same cost of 12 points, it boasts 4 hull, 2 Blue anti-squadron and a single Blue anti-ship die. As you'd expect, it has the Intel keyword. That is where the differences begin; the Jumpmaster 5000 comes with a speed of 4, letting it keep up with most Imperial fighters, as well as the Swarm keyword, giving its normal attack a slight buff when working with other squadrons.
Most Imperial ships are improved immensely by working with the Jumpmaster and Intel. TIE Fighters and Interceptors gain the ability to withdraw from combat once they begin taking damage, Advanced are necessary to protect the Intel ship, which only has 4 hull. Bombers and Firespray-31s can shoot directly at enemy ships. Aggressors and YV-666s can reposition before or after shooting. For 12 points, it just straight up replaces the 10 point Admiral Chiraneau.
Dengar adds 8 points onto the base cost of the Jumpmaster, and for those points he goes up to 3 Blue on his anti-squadron, and changes to 1 Black for anti-ship. For defense, he adds on a Brace token as well as a Scatter. The biggest upgrade over the generic though is his card text, which adds the keyword Counter 1 to all friendly squadrons in distance 1-2 or, if they already have Counter, increases that number by 1.
TIE Interceptors and IG-88 become Counter 3. TIE Advanced become Escorts with Counter 1. Aggressors become Counter 2. Fel's Flying Circus just got a lot deadlier. Rhymer Balls get better at dealing with enemy squadrons.
Much like the Jumpmaster, there are few Imperial squadrons that wouldn't benefit from Dengar parked nearby. His only reason not to make it into your list is his high cost to bring along for the ride.
Well, that's it for the Jumpmaster. On to the "oddballs" of Rogues and Villains. The Scurrg H-6 "Silly Bomber" and the YV-666 "Heavy Dogfighter".