Aesthetically speaking, the OEM windscreen is the best. The shape continues the contours of the nose fairing. I like the Zero Gravity I have on my Gen2 but it's just too smooth. It's perfectly smooth and the nose fairing has a ridge to each side that doesn't match up. I'll be doing it again on my Gen2 but I think I'll try a can of Nightshades or some vinyl on the OEM windscreen. As for color, dark smoke looks pretty much black from a distance. If you already use a smoked face shield, you still can see through a dark smoke windscreen a little on a sunny day. If you're going fast enough to look through the windscreen, you want better visibility. I recently bought a Zero Gravity smoked (not dark smoke) windscreen for my ZX-14 and it seems just right. It's dark but it's not so dark it will look black. I think I'm going to be able to see through it with a smoked face shield. It matches the tint of the smoked indicators and tail light I bought well. The new 14R is brightly colored and the ordinary smoked color works just fine for that bike. Dark smoke is for when you want it to look black but you can see through it a little if you need to. Appearance-wise, Dark smoke works for a black bike
As for the taller windscreens, I can't comment. I own a Puige double bubble but never used it. Regarding a taller windscreen, it throws the front out of balance with the tail in my opinion. We already have a large front that looks aerodynamic. Those high windscreens don't look right for what kind of bike it is. ...of course, it's not always about looks and performance, sometimes it's about utility. There was an actual shell made for the ZX-14 years back. It was like a little car windshield with a roof and a rear window. That's about as far as it goes for comfort. I'd like to try one but probably just choose to drive a car instead.