but doesn't this mean he's throwing away his character growth from the play?
Not really.
The timeline in this seems to jump back and forth.
After the disaster at Sweet Today, he is trying to find a "real" thing to make his identity. He think selling his look is shallow (and admit it, many men thought so about boy bands despite them having boatload of fangirls). So he set his ideal on something not himself, such as being in a rock band.
His boss told him to not look lightly on selling his looks.
And during Tokyo Blade, Aqua taught him to just accept he doesn't have the talent for acting yet. But he can still work with what he has.
I think his development is, he no longer fear and reject his good looks. He no longer fear the haters who say he is just the face.
Rather than trying to find a way while hiding his looks, he accept it as a weapon he already have.
It's different from just sitting and doing nothing, he instead channel his effort to bring the most from what he has.
...imagine it like this.
Melt is spawned with a machine gun. But because all the elites are fighting using knife and handgun, he think his weapon doesn't need skill, and thus making him looked down by everyone. He wants to throw away his weapon and be like the cool kids.
Now, he accept he got machine gun, and be the best in using it.