I just bought my $10k 2017 Leaf model S and I love it. It had the 6.6kW charger upgrade but was an S in just about every other way. I did have to finance the vehicle to get the $5k state rebate taken off the price but I'm planning to just pay it off in 2 months. I don't know how much I'll pay in interest or insurance before then but I don't think it will be significant. I made sure there was no pre-payment penalty on the loan so you might want to check that. Re-sale values are all over the map but most of the ones in the Denver CL are at or above $10k at this time. I assume they will drop once the new models come out but I'm planning to drive mine for a while so re-sale value isn't a big deal for me.
I just got the car in August so I don't know how the cold will affect the range but I do of course still have an ICE car or 2 that I can use when needed.
And yes, everything is negotiable. I have never bought a new car before so the whole dealer thing was new to me but it all just depends on how bad they want to sell their inventory. I've heard rumors that dealers from out of state are sending their Leaf's to CO since they are selling like crazy here, but I have no idea if that is true or not. In any case, I wouldn't wait until the last minute or try to squeeze out the last $100 from the deal. Between Xcel, state of CO and Uncle Sam (assuming you pay > $7500 taxes, which isn't hard) you are getting a new car for 1/3 the list price. And it's not a junker - I really love mine
Would 2x the range and TMS be nice? Yes of course but I doubt you'll get one of those for $10k. As is, my model S does everything I hoped it would do: get me to work, get me around town, etc. and it's lots of fun to drive. I have free charging at work although the cost of electricity is very low compared to gas.
Get the car, you won't regret it.