If it were mine, I would not mess with the trigger, just replace it. Two-stage triggers have so much travel you feel like they are never going to go off, and you will have trouble getting a clean release.
OK trigger- Bold trigger from Boyds Gunstocks, right around $35-ish.
Good trigger- Timney or Rifle Basix, right around $90-ish.
Great trigger- Jewell or NECG, $150-ish to $200-ish.
There is a trigger available called the Huber Trigger that will make your two-stage trigger pretty nice from what I have been told, but I have not tried one yet.