Quick look at the wiki, I would strongly suggest a Graviton Deflector Array MK XI [Gra] [PtrG] [SubD]
Other options would be [Em], If you want a more defenive (self defence here), then a Positron Deflector Array with [SiF] [ShdS] and [Stl] is also a good, but this is more of a tank build than a support build.
Interesting. Could you go into more detail as to the benefits of a Graviton Deflector Array over the Positron? I don't doubt that you're correct, I'm just trying to understand why. Here's what I'm seeing:
Positron Deflector Array:
Starship Shield Emitters - Improves my heals, which is really what I'm trying to focus on
Starship Structural Integrity - Improves my Hull Strength
Starship Shield System - Improves my Shield Strength
Then, of course, specific bonuses would go here.
Graviton Deflector Array:
Starship Graviton Generators - Improves my tractor beam, which I think we decided isn't really that big of a deal unless I misunderstood what you wrote
Starship Subspace Decompiler - Improve my disables, I can see how this fits into my build, as one of the things I'm trying to do, in addition to healing, is help drop shields and negate enemy damage.
Starship Countermeasure Systems - Improves Scramble Sensors and Jam Sensors, neither of which are a part of my build
Again, specific bonuses would go here.
Maybe we're coming at this from two different angles? I was thinking about making a healing build, with support as a secondary function, whereas perhaps you're coming from the idea that this is a support build, with healing as a secondary function? Which leads me to ask if healing can be a primary role in STO, or if it IS a secondary function to support (which in this case is drains and disables).