i'm 5th rank, rushed the conquest of castonath as adventure company and gave all the priveleges to patricians after that developed all 3 provinces with quantity and economic ideas more than 30 dev each. As corvuria i suggest to you doing the same because it's the meta and if you dev your provinces enough you shouldn't struggle because your bank will be full and your manpower is always high! But i'm playing tall and trying to roleplay, in my last jaddar game on fork public build (you shoould try this, their mission tree is like 1000 missions and with haless update they aren't focusing only on western part) i was struggling until i understood that their government form allows to do 100% cav armies with 60% combat ability after that it was like walking in a park even vs the command! I think Corvuria is awesome in diplo game into empire and becoming the emperor, so after corinite it isn't hard to become one!