No doubt, luffy's training means something and that is why to me he is the strongest supernova of his generation and the new one. Ace doesn't stay there with WB and train to get stronger every day which is correct, but he is sent on missions and he fights opposing marines/pirates like luffy does to get stronger correct? So with luffy's increase of power, Ace sure in mind grows everyday as well. Now that he is dead, he is now closer into getting stronger than Ace, as far as we know in the chapter. If he soloes Doflamingo and win a flawless victory, then i will agree that luffy undoubtedly stronger than Ace.
A flawless victory? That's almost like underestimating Doflamingo, his strength is incredibly high.
If Luffy can beat Doflamingo, by himself, then that should be satisfactory.
If Luffy can beat Doflamingo, by himself, then that should be satisfactory.