#1, because I couldn't bear to read any further:
In Ohio (at least), most city streets (as in, everything not otherwise-marked or a designated State Route) are restricted to 25 MPH.
Navigating a turn at an intersection in any vehicle at 30MPH is likely to get one all-sorts of fucked up if the road is not abundantly clear, because nobody around expects that.
In social aspects, it's also likely to alert your passengers to the fact that you're a madman, because you're going fast enough to scare them.
In traffic aspects, it's likely to catch the one vehicle that you didn't see off-guard -- even if the operator of that vehicle was generally succeeding at paying attention.
But on a bike? FFS: Everyone else is already trying to kill you. Don't press your luck. Assume that they're all of texting and drunk, while they also have to piss and are -very- high, while also stoned, fucked-up, and also need to dump a load. Meanwhile, they're concurrently groping for a lost (lit!) cigarette and somehow also managing to finger their girlfriend while they're also aiming directly at you because they both see you and have determined that you need exterminating. (Take all of this into consideration and you'll probably do fine for years, perhaps even decades...as long as you're not too bold about it.)
(Disclaimer: I drive an E36 BMW with sticky tires, and slowing down for a turn inside of a US city is always completely optional -- in fact, acceleration is also always an applicable option. But I still slow waaaay down when there is any visible movement, at all, when navigating a turn, and I give bikers and other vehicles all the breathing room necessary (even if it pisses off my fellow car-dwellers) for them to do what they're doing. Furthermore, I'd far rather be rear-ended by a few tonnes of someone with airbags and seatbelts than to run over a pedestrian or on any manner of lightly-armored vehicle like a motorcycle, scooter, Segway, bicycle, or similar because then, at least everyone probably lives .)