Some good thoughts here, however I'm afraid that you won't be able to use your C-130 time for more than a line in the qual block on your resume, and a great opportunity to discuss your ability to operate as part of a multi-person crew. While you and I know that you held a position of responsibility, just like NFO's and helo Crew Chiefs, the time doesn't "count" when you're looking at civilian hiring minimums.
One thing you have going for you (I hope) is your MGIB benefits. You didn't say anything about having your degree. If you don't have one, now is the time to start. Getting started in this environment (with a ton of high-time pilots on the street) is tough, and it's a good time to take a slightly different tangent and work on quals. Try looking around for a school where you can whack out a 4 year degree ASAP (remember to get whatever civilian equiv you can for you Marine Corps job experience). If you can find one with a flight department where you might be able to pick up some part-time CFI work, that's good too. You really only need your ATP at this point, and you need to build hours for that, so the standard CFI, traffic watch, banner pull, drop zone route might be your route.
As someone else alluded, age dependent, you might also consider doing the degree-OCS-flight school-finish 20 route. If you go reserves or guard, you can get some retirement credit for the time you're in school, and with your prior time, you shouldn't have more than 15 or so to hit 20. Many states provide full tuition for guard members, and with your MGIB you could get your degree pretty painlessly (financially anyway).
Good luck, don't forget to consider the reserve option even if you stay straight civilian. It's good for the country and for you.
Semper fi...PM me if you need any help. I retired as the site commander at NAS New Orleans and still have a few contacts in 4thMAW.