I do not think you would want to be level 50 with 80 in the mentioned skills (doesn't include destruction) while wearing Imperial or Stormcloak gears and wielding Iron or Steel weapons.that would just be insane. Remember, some instances of the game are 'leveled' and grow in power along with you. You can train your One-Handed, Two-Handed, Archery, Destruction, and most importantly, Sneak abilities here for as long as you like! Neither NPC will die when their health drops to 0, but I do advise you to be very careful about how high you level up. It doesn't matter who you escape with, as they will NEVER die as long as you DO NOT ESCAPE Helgen.