Bad formatting / readability of Harp parts

Finalisation my first orchestral piece, the readability of the Harp parts is not good. The distance between the staves is “dynamic” depending on the music but this occasionally leads to a too small distance between the two, see two examples below.

How can I set, e.g, a minimum distance between the staves such that the stems get longer?
If somebody needs to see the score, it can be found here https://musescore.org/en/node/361239.