As much as I love Light, I don't want Lulu to be a Light clone. If I want Light I'll go watch the very wonderful Death Note anime currently running or look at the manga. So I really LIKE the fact that Lulu is struggling so much and hestitant. His fall from grace seems more subtle and gradual. But I do notice some harping in the fandom about how Lulu isn't evil enough and I don't get it. Why do they need him to be more evil? Maybe because the rumors/spoilers keep saying that he will takes certain steps towards heartlessness/evil and they expect it to happen right away for some reason. But if he's meant to be evil then he will eventually be, so they should just be patient.
Though I don't think Lulu will ever be like Light even if he does become a "villain"...he still has some goodness in him that won't be crushed so easily (like his love for Nunnally).
Re: tl;dr
Though I don't think Lulu will ever be like Light even if he does become a "villain"...he still has some goodness in him that won't be crushed so easily (like his love for Nunnally).