You simply cannot argue how much you learn from getting your commercial ticket, to about the 600-750 hour mark.
I am just shy of 1000 hours now, and I really do feel as though I'm in a stagnant position. I finished my commercial with 212 hours, and got hired for this photography job. My second solo flight with the company (I probably had around 220 hours), I was shooting revenue down near Long Beach, south of LAX...lost my alternator. Our camera system has a huge electrical draw, and my battery was dead within 5 minutes. First call was from ATC reporting radar coverage lost (transponder goes first most the time), notice the low voltage light, radios cutting in and out, etc. I report to ATC that I'm going to return to SNA.
No clue if they heard me or not, cause right after that everything was dead. I instead went to Torrance and landed...did the procedures great, and thank goodness I had just been drilled to death on light gun signals.
It really was kinda scarry to be a newly commercial pilot, flying around SoCal not talking to a soul.
Anyway, when I got on the ground, I called the tower and he said that approach had heard my call to return to SNA, and that next time if I say im planning to do something, to follow through with it...cause I guess they started clearing traffic at SNA. Lesson learned =)
But anyway, back to my point...I learned soooooo much from that 212 hours, up until about 600 hrs, and now I am definitely ready to move on....fly something more complex, and begin learning all over again.
Could I have gone straight into a regional after getting my ticket, and been fine....probably. Am I an extremely more competent pilot now? Most definitely. My decision making, scan, radios, navigation, knowledge of systems, confidence, and comfort level in an aircraft are all 100x better than when I had 212 hours.
There is simply no substitution for experience, and to be honest, a large jet with paying pax in the back is not really the place to learn these basic yet necessary aviation experiences.
As far as DMEarcs thing about requiring 500 dual given...I dont believe that instructing is the only way that you gain valuable skills in aviation.