Beware of glock aftermarket trigger parts/work. My dad had the local glock armorer do a trigger job on his glock 21 gen 2 and whenever I shot it after that, the trigger would not reset for me. It worked fine for him but I couldn't shoot the thing because I'd pull the trigger and it would go bang but the trigger wouldn't return forward/reset. Had to be cycled again to reset trigger. Was weird.
Anywho the standard glock sights are kind of useless, they are usable but most don't like the ball in bucket sight picture or the fact that they could break fairly easily.
The guide rod I would leave alone, or maybe order a spare Glock brand spring assembly for when yours is ready to go, which will be a long time. I have seen aftermarket guide rods cause issues with not fully seating the slide.
Basically I would pick sights you like and just buy some ammo. Stock is good, factory parts are good, you shouldn't go upgrading your motor with aftermarket parts, use factory parts, same with guns. Factory parts will usually be more durable and fit better