Hi sprout, good to see you here.
Thanks for the feedback! Here is the interesting thing, the formula I came up with was:
time it takes to jump - time it takes for enemy to reach you = range of 0.5 to 1 second (the shorter the harder)
If I adjust the time it takes to jump then I have to adjust the enemy range and the tiles design. I did had a feature on to-do list but didn't end up implementing it, it was a feedback loop for jumping, either a sound or load bar, so that player have a sense on how close to a charge jump.