What are your opinions/experience with the Green to Gold program?

Hell yes if you get your usual pay for attending college, and you get credited years for retirement. That is a sweet deal.

If you're looking to do the AD G2G program you will have to use your GI Bill to pay for it.

Yeah your description doesn't fit the title. There's plenty of enlisted with degrees, plenty of warrants with degrees. Do you want to minimize cost? Then stay the course and let the Army pick up the tab, or if you want the degree done fast, take a loan and knock it out, then you can apply for OCS. Ensure everything on your JST that can be applied is applied, I had to dig and found a spare 3 credits, called the school and saved an extra semester. Once you finish ALC, do the same and have them reevaluate your JST, along with the MOS credit for being a 3 level. Go to jump school, SERE, etc for more elective credit. plan to drop your packet as soon as your degree is conferred - i.e. have everything else done and just wait for the final transcript. My warrant board essentially considered my MA complete since I was in the final semester.
Remember, you can be a pilot without having a degree if that's what you're looking for (street to seat puts high school graduates into WOCS and flight school) - pilots are boarded at every single warrant board. Have you talked to any 15As? Once they pin O4 their seat time is essentially done (save for special assignments), if that's what you're looking for that's fine. Lots of people just want to fly and the better route for that is 150A.
Also, (Officers please correct me if I'm wrong) but from what I've learned is that during OCS you make a "wish list" of preferred branches and the Army "tries" to get you what you want, but it can happen that people want aviation and end up finance.
I'm also told that many apply for 15A, but totally forget about 67J - the medevac pilot
Best of luck.