What if Lúthien had been "ugly"?

[Maédhros]

In the Silmarillion we have:

It is told in the Lay of Leithian that Beren came stumbling into Doriath grey and bowed as with many years of woe, so great had been the torment of the road. But wandering in the summer in the woods of Neldoreth he came upon Lúthien, daughter of Thingol and Melian, at a time of evening under moonrise, as she danced upon the unfading grass in the glades beside Esgalduin. Then all memory of his pain departed from him, and he fell into an enchantment; for Lúthien was the most beautiful of all the Children of Ilúvatar. Blue was her raiment as the unclouded heaven, but her eyes were grey as the starlit evening; her mantle was sewn with golden flowers, but her hair was dark as the shadows of twilight. As the light upon the leaves of trees, as the voice of clear waters, as the stars above the mists of the world, such was her glory and her loveliness; and in her face was a shining light.

I know that elf are supossed to be beautiful and stuff but just for a moment think that if Lúthien weren't as beautiful as she was or even "ugly", would Beren had been enchanted by her? Was his love for her because of her unsurpassing beauty? Or was it something beyond that?

Then the spell of silence fell from Beren, and he called to her, crying Tinúviel; and the woods echoed the name. Then she halted in wonder, and fled no more, and Beren came to her. But as she looked on him, doom fell upon her, and she loved him; yet she slipped from his arms and vanished from his sight even as the day was breaking.

She loved him from the start, I wonder would he have loved her if she was "ugly"?