Too many systems. Soldiers are sets, weapons are sets, factions are sets, everything has its own sub category. Way too confusing to and way too easy to accidentally spend money or purchase an item.
I agree, far too many menus and sub menus needed to go through to upgrade my soldiers.
CAMPAING: pick the campaing you like more, pick the army you like more, play the game
SQUADS: play the game, unlock squads, main the squads you like, upgrade squads
SOLDIER: play game, level up soldiers, complete battle task, use logistics to get soldiers, use logistics to get equipment, pick soldiers you like and equip them with items and weapons
ACADEMY: combine 3 leveled soldiers into 1 of 1+ star
WEAPONS: disasemble many of one weapon to upgrade one of that type
That is literally all the game, how is it too complex?