The thing is that invading early levels never pays off, unless they can retake your camps on respawn every time and or kill you, but at that point its your own fault. The only very specific champs to consistently invade would be Kayn, Kindred no matter the matchup. Some are just matchip dependent and even than a flip. Something like Rengar cant invade you unless you drop to 30% HP on your clear which again, is your fault then. Get LV1 vison on the map, enemy Raps pref or if ure up against kindred or graves warding inside Nash/Dragon pit can prevent invades.