Yeah, the selling point is the int and save, I went with the sihala charm for the stam personally, DR is not that big of a save but I suppose it's nice to have. Shojar shines because of it's CR, I can think of plenty of encounters that need CR and it's a pretty sweet thing to have on a charm, and AGI is not that bad in and of itself, since you are a necro it'll let you survive more before you flop, if you have to pull you have a better chance at dodging stuff.
I think it's fine as is and that if you wanted STA and your int was capped you should have gotten sihala charm.