Implement algorithm using GeoHex approach
The MineT(X) algorithm uses ranges that can be represented by tiles. If we want to use an apprach that combines the circular ranges (representing reachability a bit better than tiles) and tile ranges (not overlapping and therefore easier to compute; using spatial indices better) then GeoHex could be the way to go.
So just changing the shape could lead to a new algorithm MineGX :-)
I guess that the performance of such an approach is somewhere in the middle between MineRX and MineTX, but that is only a guess. Maybe it is even better than MineTX :-)
What remains unsolved at the moment is the use of adaptive GeoHex sizes, since the hexagons of different zoom levels overlap with the ones of the next/previous level (in contrast to the tile regions used by MineTX).