i think it would be cool for the healer to instead be in some sort of small vehicle that increases speed so that they can maneuver the battlefield dropping tech along the way. throwing down a field medic kit almost like a light well, or even placing a shield barrier that last x amount of time or x amount of damage, using a turret to toss heal buffs onto the boss sort of like a judgment but for everyone hitting the target -- being able to shoot heal spells similar to ana.
I have thought a lot about a 3 role class (mine is technomancer which is close to a tinker but with some differences) and I am trying to think of ways to make the class feel almost like a druid in terms of class RANGE, honestly a druid feels like 4 completely different characters, where as some classes have 2 or even 3 similar play styles with small variations. So upsetting the playstyle of a couple roles while sticking close to the current formula is what i have in mind. say a tank who sets barriers that have magical taunt qualities, or a the zippy landmine healer. i dunno, arbys is pretty cool.