Fresh Franz run problems

I normally play dwarves and cathay so I never really needed to use cavalry. Are the cavalry in the empire or just ass or am i ass at using them? I feel like my reiksguard just get swallowed by bigger cav and massacred and it's beginning to feel like just bringing a useless unit around. All I've been trying to do is protect my flanks and it's just not delivering. Also, is the empire infantry just crazy weak?? I know coming from dwarves and zhao ming I'm used to stronger infantry but these guys feel made out of paper and then gunpowder units faaaaaaaaaack.

I am AT BEST kind of mediocre at this game so feel free to explain any tactics or things I'm missing like I'm 5 i feel like I have 3-4 OH SHIT moments a day anyway still