Everything looks good. I honestly don’t think that Luke backing off when Rey ignites the lightsaber is a sign of weaknesse. He bested her easily in a duel.
I saw it as Luke backing off as he fears Rey is falling to the dark side. He sees Ben Solo’s rage in her, and he fears history was repeating itself…the whole reason he went into hiding. He isn’t afraid she would strike him down. He’s afraid that she wants to, and he’s failed yet another who wanted his help.