I doubt you find any hybrid below $15k, ever. Let alone with diesel.
The LI-PO batteries alone will cost more than that, for the time being at least.
And more than likely the batt. of the future is LI-FI, Li-Fi cells are much less violate and last perhaps thousands of cycles verses hundreds, and can be fast charged without the danger associated with fast charging Li-Po batts.
You're right.
However, what I had in mind was a Honda Civic with about 20k miles on it. It would get 35+ mpg and be a high reliability car. I would not at this time pay the up front extra to get a hybrid. Battery maintenence issues, other unknowns makes it to me a very iffy investment.