You will not progress very far in the planche until you have mastered the L-sit. It's fun to practice but I didn't find it very useful to work the planche with my gymnasts who couldn't hit a 30 L-sit. Even then, progress was slow. Of course Erik didn't like doing L-sit and hangs that long which also compounded the problem some of the time. It's called being 10 and lazy or tired (due to lack of sleep or food).
Yes, I'm short and wide and haven't been built like a typical gymnast for 15 years when I was 5' and 125 but I can still hit a 1m L-sit. It's not my core strength that holds me back on the levers, it's my lack of upper body strength. As well, I've got a lifter's lower body and I'm fatter than I should be.
Yes, I'm still short so that means shorter legs than many besides my ape arms. If you're 6 feet that L-sit is going to suck that much more. Still, that's life.