Scipy 1.0 Roadmap

Note: to be discussed on the list, don't merge.
Has there been a proposal for converting COO format into a rasterized form, with (flatind, value) pairs instead of (row, col, value) triples? Benefits are:

 - trivial to create, manipulate, and explain
 - supports arbitrary ndarray shapes, not just 2d matrices
 - many operations on COO matrices are trivially adapted, or even simplified (e.g. conversion to CSR/CSC, reshaping, duplicate summing)
 - easier to use a fancy data structure with (e.g., storing indices in a red-black tree or index-value pairs in a priority queue)
 - lower memory footprint than COO, assuming a naive data structure (2*nnz vs 3*nnz for COO)

It seems like this format could even subsume LIL/DOK formats, with the correct backing data structure.