I started poliastro as a wrapper of some MATLAB and Fortran algorithms that I needed for a University project: having good performance was a must, so pure Python was not an option. As a three language project, it was only known to work in my computer, and I had to fight against oct2py and f2py for long hours.
Later on, I enhanced the plotting capabilities of poliastro to serve me in additional university tasks. I removed the MATLAB (Octave) code and kept only the Fortran algorithms. Finally, when numba was mature enough, I implemented everything in pure Python and poliastro 0.3 was born.
poliastro has been historically focused on interplanetary applications, so we would like to improve its Earth-specific capabilities in the future, for example:
High order gravitational model for the Earth
Input/output of TLE and other GP data format
Attitude & dynamics
And in general, we would like to stabilize the API and release a 1.0 version at some point!