Yeah, I think manufactured e-bikes (not converted/retrofit) have become a lot more popular in recent years. I think price points are all over the place because of so many different factors. Things like do you want a folding bike, a cruiser, a mountain bike, a motorcycle-style, a cargo bike, or a commuter bike? Not only is the form factor a thing to consider, the quality of components are important too.
Even trying to spec out a conversion is difficult too because there are a lot of different kits and a lot of different brands for the components. It’s all confusing and I think it’s due to e-bikes being so new to the scene. I’m sure when cars first came out, it was hard to know which brand to go with, but now that they’ve been around several decades, it’s easier to pick which one you want.
To go over your points, I’d try to figure out the form factor you want and be realistic with what you are looking for. In regards to price, the bikes I considered ranged from $1000 - $2500 ($3000 is probably pretty good, but you reach “luxury” at that point). If you can try one, I’d recommend it, otherwise it’s hard to figure out what you don’t want from a bike. Regarding quality, I think a good indicator is warranty length and leniency. 1 year is standard, 2 years is good, and 5 (very lenient policy) is the best I’ve seen so far. And another is if they say the brands of the parts they use. So things like the drivetrain, the tires/wheels, and brakes are things I would try to see if I could buy from that brand. Or you can watch reviews to get a feel if the brand is good or not
Lastly, in terms of battery safety, it’s recommended to go with a well-known battery cell brand. Don’t buy an e-bike if they won’t tell you what brand the cells inside are. Cells are what makes up a battery and if you don’t recognize the brand name, it might be a good thing to pass on it. Think brands like Samsung, LG, Panasonic (CATL and BYD are other big ones too). The battery itself might be from a random company, but if the cells are from a good company, you should be fine. The battery shouldn’t be left outside, it should be brought into a climate-controlled environment if not in use. And the likelihood of it catching fire is low if you take precautions.
In terms of actual safety, accidents do happen, but the frequency is on-par with pedestrian and vehicle accidents. Best thing you can do is use caution and be defensive when riding. Things like wearing a helmet at the very least, having lights, being visible, and avoiding any roads with high speed limits
There is usually a 10% off promo code floating around to get it from $15 to $13.50. But hey, $1.50 is $1.50