Best thing to do is test it, if you like the results stick with it, I really wish the DMR was versatile!
If you see yourself getting value, then the model is working for sure, but at 9 stones I have Grimwell instead, he will kill the enemies scheme runners or key models, deny schemes and strats completely, lock down certain parts of the board and can use soul stones, he could even get you some cards! For 2 more stones (DMR and an upgrade) I have a pale rider wandering around!
For a stone less I get Alan Reid, min 3 alot of the time, execute trigger can be brutal late turn, especially if you accidentally stone in that crow.... but even early turn its draining the opponents cards, alot like his bonus action, an aura for no bonus actions nearby reduces enemy AP, drawing at least one card a turn, slowing models down, drawing extra cards.
There's never a wrong answer so don't stress! But some combinations can give you really good value 😁