I sort of like the current lighting -- it's modern in an industrial sense, and helps drop the high ceiling a bit visually. What do you not like about it -- seeing the fixtures? is there not enough ambient light? I mean, you could spend a fortune putting in recessed lighting, and/or up/down wall sconces all the way around, or you could put a couple of high flushmount fixtures and get a folding scaffolding for changing the bulbs...

I think I'd just have the green fixtures painted black, or an industrial galvanized steel look, and then live with them for a while. Other solutions are going to get pretty arcane.

I can’t see those lights being very useful for lighting why not check out cable lighting it allows you to bring light down to a height that works and still be quite unobtrusive and of course LED bulbs to keep that hassle to a minimum you also need some actual lighting at the space like floor lamps and table lamps lighting is really about layers of light not just one source