I felt the same last season, like I needed either a bigger board or a bigger kite. I'm 60kg and have 134 Spark. 10m bandit III. problem solved this season! Srapped and unstrapped 5'10" surfboard, now some days I'm lit on a 7m core GT. still love my Bandit, so much, but have also added a wave specific BWS Noise 8m for those 15 knot days with swell (oh how we love thee).
Some good advice here, don't edge too hard before up and planing, or buy a kite/surfboard and enjoy them in their native environment, the ocean.