EU4 combat simulation must be one of the most complicated formula. General skills, military tech level, morale, terrain, number of troops, combat skills, troops compositions and pips. Pips are represented by how powerful units from that technology group within that period of time, or military tech level.
Here are the stat of pips from different tech groups in different military technology levels. Since different technology groups advance in different speed, so they usually aren’t in the same military level. Overall, nomads have the best units in the beginning of the game, then different tech groups have their leads in the middle of the game and lastly, the Western tech group gets the strongest units and the Eastern tech groups get the second best.
The best unit(s) within that military tech group is bolded.
Please feel free to point out if there are errors in the chart!
In addition, these stats shows how infantries are weaker than calvary in the beginning of the game. Except for Americans, where horses were introduced in the middle/beginning of the game. But eventually, calvaries are becoming less and less important in the battlefield. Eventually, cannon became the most important unit in the end of game and all cannons from differnent tech group share the same stat!!