No way man. Flutter kicks will rip your shit up. I think they put 90lbs on my raw squat.
You are right. As a gymnast and competetive strength athlete, you are going to need more intensity. I don't know how we as a society have become such pussies when it comes to 'core' work. Want to work the shit out of your abs? Hold something really really heavy out in front of you and walk with it for a while. Front squat holds are good. You will probably need to make them harder. I would suggest front squat walk outs with suspended weights (plates hanging from jump stretch bands, chains hanging off the bar not touching the floor, etc.). Just walk out, let the weights settle, then walk it back into the rack. These are brutal. I really like an exercise that I have been calling 'fat guy abs.' Lay on the floor with a band wrapped around your feet (the other end is connected to a rack) and basically do a laying knee-up. These work my abs in a similar position that I deadlift in... minus the laying on the floor part.
Heavy ssb squats without a belt work well too.