Its closer to two years out of data and the Nexus 10 is the latest Samsung Nexus

Traffic accidents make up ~32,000 deaths per year, that means they don't make that list (Albeit barely)

CDMA2000 is on its way out even vzw and sprint are moving to gsm with LTE. At this point you can only do data and only in areas with lte service but eventually lte service will provide voice and will be pretty ubiquitous.

Just thought I'd link to a tutorial on having fallbacks http://android-developers.blogspot.com/2010/07/how-to-have-your-cupcake-and-eat-it-too.html I don't think adding permissions not in v1.5 are an issue. Android 1.5 would just ignore them while newer versions with support for them would properly utilize them.

Strangely enough it's actually $649 you seem to have found a vendor on amazon who is inflating the price... (or perhaps thats a 32gb model?)
https://play.google.com/store/devices/details?id=samsung_galaxy_s4&feature=device-featured
the htc one is a mere $599 for their 32 gb model....
https://play.google.com/store/devices/details?id=htc_one&feature=device-featured

Interestingly enough the nexus phones aren't sold without profit, in fact the nexus 4 has ~$150 profit. They just aren't sold at ridiculous levels of profit... Note that price is based on a tear down and the price of components.

interestingly enough there is a way to target 1.5 yet use 4.2 features if they are available, you just fall back to lacking functionality on devices without those features.