I like mechanical triggers. Hard to go back to inertia for a target gun.

Kolar, Krieghoff and Blaser triggers are exceptional.

I also think modularity is important because, lets face it, you will most likely change your mind a bit and having the option to swap, sell is a good feature.

All three give you that.

Weight system is nice to have to fine tune balance.

Adj Comb is nice to have as well.