Dex and Faith

So I tried to go for a dex faith build but it just doesn't seem to be working. On top of the fact that I have found hardly any miracles beyond the obvious ones.

Atm I have stats 30 vigor 20 dex 25 faith and a few levels in mind and endurance.

Starting class was wretch.

I just beat rennala and managed to climb to the plateau but I feel like I have no real damage and now it's taking like 20k runes to level up.

It feels unfocused idk. So it seems like dex and faith basically don't go together at all?

My only weapon is rogiers rapier with sacred blade.