i think, probably, you are not the target market for the kindle devices, especially not the 'basic' kindles (paperwhite etc, not the scribe/oasis/et al)... i buy kindles explicitly BECAUSE all they are is a reader. and i would pay double for a color kindle paperwhite in a hot minute (like, immediately, right this instant, i would preorder one if it were available). ive wanted a color e-ink device ever since the first ones went on the market but havent bought one, and it isnt because of price... its because i dont want an everything and the kitchen sink device, i want a READER. and i especially dont want an android reader.
youre also incorrect about the battery usage. a color e-ink screen uses no more power than a black and white one. the thing that causes the terrible battery life on the other color readers is ANDROID. the kindle os does mostly NOTHING when you arent turning pages (or adjusting settings), and if airplane mode is on, its for really real doing nothing at all. aside from readability, thats the whole point of e-ink, it takes zero power to hold a screen. so that power drain is from all the OTHER things the device is doing.
i think its great that there are kindle alternatives, because clearly, not everyone buys a device for the same reason. but i suspect a lot of kindle die-hards use them not because of the price, but because theyre very focused devices that are EXCELLENT for what they do: reading books. and i suspect a basic paperwhite with a color screen would sell quite well indeed.