Who is better? Lucian or Ezreal?

Overall gameplay and laning = Lucian

For securing kills and winning team fights = AP Ezreal

Ezreal has been my main ever since he was released. He is my most played/favorite/best Champion in the game. So I'm biased and want to say Ezreal.

However I think Lucian is probably more competitively viable.

Lucian has probably the highest damage output potential of any ADC, but Ezreal is extremely safe and has that blue build going for him.