Historical Project Mod Plus (HPMP) is a stand-alone update built upon HPM 0.4.6.3, building upon it with both bug fixes/QoL improvements, and an Expansion of several HPM mechanics I really liked, but felt underdeveloped. Many improvements towards the late game.
Addon which will cause the music in the game to change after World wars are discovered from normal Victoria 1/2 music, into Hearts of Iron music which...