I know Vans, Scott, and Mike Seager have writings that advise against Bunny Hops, but I'm very much with you, Pierre. That's how many famous airplanes made their first flights - some even unintentional - and that's how Boeing (sort of) does it today.
On an all new airplane, they do runway runs at increasing speeds, testing the brakes, the flight controls, the thrust reversers. Eventually, they get into quite high speeds and rotate the airplane, first a little, then a lot - rolling along with the nose in the air for a substantial distance, then gently lowering the nose gear back to the runway, and performing a stop. If you look closely at one of the 787 rotations, you might even be able to see daylight under the MLG tires - which generated quite some speculation about whether or not this was indeed the unofficial "First Flight."
Tony LeVier's First Flight of the U-2 was just such an unintentional first flight.
If you're ever around Renton, Washington - you can watch production 737s make their First Flights - they make two/day. The airplanes normally takeoff to the North over the Lake. The crew starts up, taxis to the north end of the runway, apply power and accelerate to take-off speed heading south. At around V1, they reduce thrust to idle, apply reverse thrust and substantial braking, and stop at the South end. Having verified all the critical systems for flight - engines, brakes, reversers - and stab trim - they do a 180 and take-off to the North. (If you watch them do this, BTW, you will see them turn to the right and fly up the East Channel between Mercer Island and the Mainland. After takeoff, you will see the gear come up - and then immediately come back down. Something wrong? No - they make sure the gear will extend so if they have a problem, they will have several hours to troubleshoot the problem, instead of finding out at the end of a three hour flight. It also cools the brakes, heated up during the prior aborted takeoff.)
So - I think your thinking has good company Pierre. An accident that may result from this technique has a better chance of being two-dimensional rather than three-dimensional. You may mess up your airplane, tear the gear off, etc, but that beats diving into the ground. You can learn a lot about your airplane and gain personal confidence in a reasonably controlled environment.
FWIW, I have made about 140 of these high speed tests on the 737, where a lot was explored without ever leaving the ground (I think!) All were over 100 kts and the fastest reached 144 kts - on an airplane where the weight made 107 kts "flying speed." One bump in the runway or big expansion strip and we would have been flying!
Bob Bogash
N737G