Low speed is the easiest way to screw up, because it’s a lot harder there. So keep doing the parking lot practice. That will help build confidence. I had a church parking lot down the street from my house where I practiced a lot when I first got the bike, and every other long-term rider I’ve talked to has done the same. The practice is also fun, and a good excuse to fool around on your bike.
As for worrying about getting hit, there’s nothing special about a bike that makes that more likely. I was hit four times in one year in my Honda Accord. I was never at fault. Twice by deer who decided that jumping from cover into the path of a vehicle was a good survival move (once in town), and twice by drivers who were not looking where their cars were going. In the case of the two hits by cars, I had no viable escape route that would have avoided the situation, and it wouldn’t have mattered how big my vehicle was, because they weren’t paying attention to what they were doing.