Ranged can already unload at a 30m range on melee. But why would they be moving at full speed? You have to think outside of the box. Melee should have the mobility and snares to even the playing field. They are re-balancing things with all of these changes, so solutions to minor problems like this shouldn't be an issue. The most important thing is to have fun gameplay and work down from there. Instant cast abilities are more fun and now is the perfect time to open up some customization for the players.
Also, imagine upgrading Tracer Shot with a reworked Mag Shot in the Ability Tree. And in the same row of talents that choice is put against say Thermal Detonator, Fusion Missile or another ability with a utility function. There are many ways to make things work.
My point here is that we do not need 3 different healing abilities. Having Emergency Scan and Rapid Scan makes the most sense thematically. What and how Rapid Scan works is up for debate. If Rapid Scan works exactly like Kolto Shot, but with extra healing, then go with that.
Jet Boost deals some damage and knocks back enemies. Not sure what else you would call it? Explosive Dart does the same thing except from range. There is no reason to have both. So it makes sense to me that we would have Jet Boost baseline and then Explosive Shot as a ranged upgrade in the Ability Tree that deals increased damage with a similar function.