I am a industrial product designer with 17 years experience designing disability assistance systems. I have been into hydro systems for 7 years now as an amateur veggie grower and weed 3 years now.
I have been working on an aero system which I believe can be made here for less locally and fills a definite gap in the market. Realistically I feel there is another 12-18 months of work ahead of me.
I don't think you need China for this but perhaps for others. Besides it would be nice to get "made in Britain" going again. Unfortunately looking overseas only weakens the long term position in favour of the short term margin.
My apologies if I seem condescending, I am not trying to be, I just have argued this point for a decade or so to hundreds of clients and employers.
Touching on bespoke systems, this is a huge market waiting to be be investigated further. I don't know of anyone producing these systems on a large scale. But this requires a large initial investment for stock to put them together.
My ideal job would be going into peoples homes and designing and installing custom indoor hydro grow rooms adequate for full family sustainability. I'd even like to extend that to aquaponics...go the whole hog.....sigh