I think MAP is spot on with the assertion that the historically successful clubs will continue to be successful with the changes coming for 2017. I don't think Blues, Surf, Slammers, Beach or Legends will suffer at all from the changes with GDA. Blues is the smallest organization of these teams I highlighted, but they have been successful for so long getting girls exposed to college coaches, that their name alone will keep them in the upper echelon of teams.
As for the statement about good trainers, let's look at it another way. Usually the best trainers (coaches) are people who want to increase their knowledge base, so they get a higher coaching license. Why is US Soccer stating that GDA coaches need an "A" license? They correlate a better coach with a higher license. This is really no different that those of us that went to college. A bachelor's degree is great, but a masters degree should allow you to command a higher salary from prospective employers. Again, with a doctorate degree you should be able to command a higher salary. Coaches should be no different, the higher coaching license they attain, the more money they can make coaching our kids.
Can the smaller clubs attract A, B and C level coaches and pay them what the market rate is for those coaches? Probably not, at least not in the long term. That is where these mega clubs come in. They charge more for their product and thus should have the funds to attract the highest level coaches which in turn usually attracts the best talent.