The moment I graduated and lost access to ArcGIS I got out QGIS and become ridiculously empowered. Yea Arc has Python APIs for some things but QGIS, while rough in the UI department, gives you powerful access to everything. And it plays so well with other things: check out my presentation on using QGIS in robotics (pdf) https://roscon.ros.org/2018/presentations/ROSCon2018_Unleash...