To play devil's advocate a bit longer ...
What is at issue is whether one cannot substitute 'good' without loss for kalon, (or perhaps, in some circumstances, such bland terms as 'admirable' or 'fitting'), so that there are no grounds for holding that beauty, or moral beauty, is distinctively important in Aristotle's Ethics.
Gabriel Lear thinks that moral beauty is thus important: "according to Aristotle, not only are virtuous actions kalon-- beautiful, fine, noble--but the virtue agent chooses them for this reason". She offers a theory of moral beauty for the Ethics, claiming that:
- Aristotle holds that a good action is beautiful in view of its order, symmetry, and boundedness, which make such an action beautiful,
- Aristotle thinks of beautiful actions as essentially having a 'visibility' and 'showiness', and
- Aristotle regards "the visibility of the fine [as] also important as a condition of its causing (its proper) pleasure."
She therefore has to put great weight on 2: "If we examine his other remarks about to kalon, we find that visibility or 'showiness' is essential to his conception as well." But she cites the Poetics in defense of this. When she turns to the Ethics she says "Aristotle does not emphasize showiness or quasi-aesthetic appeal in his discussion of virtue as an intermediate." Indeed. She then misdescribes a remark in Aristotle's discussion of magnanimity: "the great-souled person, who is the best and most worthy of public honor (IV.3.1123b28), acts on a grand scale specifically because beauty depends on size (IV.3.1123b5-7)". But that's not what the passage says: Aristotle does not say that the achievement of beauty is a motive of the magnanimous person. (On Lear's misconstruction of the passage, Aristotle would be committed to the view that the kalon could be achieved only in great actions.) Finally she quotes 1177b16-17 and says that "actions of the politikos and the soldier stand out in their magnitude and also in their beauty". But Aristotle writes kallei kai megethei, and why should we think that 'beauty' (kallos) here signifies the same as kalon, as that is applied elsewhere, to virtuous actions that don't 'stand out'?
Similarly Lear gives no compelling texts in support of 3. She defends the claim by appeal to a passage from the Rhetoric: "Whatever is praiseworthy, being chosen for its own sake, is kalon, or whatever, being good, is pleasant because it is good" (1266a33-34). But that passage seems, rather, to undermine her view, since it defines kalon in terms of goodness and pleasure. Accept that it gives the definition of kalon in the Ethics, and one has no need of a theory of beauty: kalon may be eliminated through definition.