I apologize for the very crude drawing.... But I'm a smasher, not an artist :D
Anyways, these are all the "hazards" so to say and where they spawn. General safe areas fall right below and slightly left of where the piranha plant spawns, up in the air to the right of the right fireball spawn place, just to the left of the missile and to the right of the piranha plant spawn, as well as
possibly the right ledge, depending on the behavior if you are grabbing the ledge while the spring happens. The left ledge is also feasible (I think) depending on your recovery options (when the diagonal line spawns).