Stock valves are fine and can be tuned not to bounce easily enough. Pretty much any aftermarket valve is good, just lower or higher pressure.
Hammer weight... heavier might be slightly better for pump since the spring would be weaker? It's pretty minor, I would just make sure it is stainless and has a nice lug.
Roller sear is pretty awesome, have you made sure you have all of the set screws setup in the trigger frame? Every slider I have seen lately is missing set screws or adjusted wrong. It makes a huge difference.