If you feel comfortable doing some gunsmith work on your pistol - nothing to worry about. Start with watching videos (YouTube, CGW Tutorials) to know everything about the gun, so during your job you won't miss anything. (especially non Omega action)
Dry Firing Pros / Cons ? Mostly Pros. You make your shooting behavior natural (no surprises during live fire), you learn proper stand, grip, finger discipline. Cons: you wear the gun... but you do it anyway during live fire... it's just a tool, so in my opinion there is no"cons". Just remember to use O-ring, snap-cap or laser cartridge during dry fire (do not let firing pin hit empty space in chamber)
Polishing - be very, very careful... Perhaps install Pro-Package first then do polishing if needed.