I want it to grow everything I want out of one reservior. Grow as many plants as it can, but take up as little space as possible.
That sounds like a great system.

Hi-droHome,
Vertical modular units 1 meter wide, at base is an insulated reservoir that serves as a step to reach the 2 meter height plants ( & counter weight where attach frame) ; mid section growing capacity, with all pumps (water & air) set back & accessible located above the reservoir; built in retractable or pivoting open plant support to lay (forward ) some foliage on &/or train to climb (up side posts); exterior facing side of unit with both a track for retractable shade cloth & also transparent plastic; these can be selected depending on weather to swing up & out (awning) or pull down (wind break); bracket extensions from top bar to support supplemental lighting for any location/season; water proof spectrum specific LED light installation designed for irradiating the growing area with supplemental light; a cold season 1/2 hoop arc enclosure frame for 1 meter width covering reservoir & giving plant protection; aerodynamic wind spill feature at top for when wind strong (like non-inverting umbrellas)....

Thank you for the posts. Anyone else have any suggestions or thoughts on what you would want to see in a balcony patio hydroponic system that would be a selling point?

When I think of balcony, I think of tomatoes growing down, maybe a bit hard to harvest.

Biggest turn off is maintenance, I would like to have to monitor or adjust once a week at most, preferably once every two weeks.

That said, I can think of big reservoir to hold extra water and nutrients without having to top off every day, finding the right plants that you can suggest for growing (e.g. tomatoes are heavy feeders vs herbs that don't like much water).

And here is the big one for me, since I'm a tech fan: I want to control and watch the status on a computer screen (wireless/internet/intranet), have a software that can tell me what are the corrective actions if I have any defficiency.