How to translate “menos del comer saludable”?

Question

I have a few questions regard the blow reader comment to an article on El País:

Si de verdad quieres invitar a comer a alguien, es importante adaptarse a sus gustos culinarios, y no pretender hacer proselitismo, y menos del "comer saludable", ya sea sin azúcar, sin sal, sin alcohol, sin grasas o cualquier otra novedad sacada de algún libro de autoayuda. Si no se está dispuesto a cocinar al gusto,razonablemente, de los comensales, mejor no invitarlos a casa, a no ser, claro está, que se esté dispuesto a tragarse, en silencio, la comida superdulce, hipersalada o grasosísima que te sirvan, en justo pago, el día que te inviten ellos. La fiesta siempre es para los invitados.

And my translation is:

If you really want to invite someone over for dinner, it's important to adapt your cooking to their tastebuds, don't try to convert them, and ____ "eat healthy", as in no sugar, no salt, no alcohol, no fat or any other novelty taken from a self-help book. If you are not willing to cook, within reasons, to your guests' tastes, it's better to not invite them over, unless, of course, you are willing to swallow, in silence, the super sweet/salty/greasy food that they serve you when they invite you back one day. A party is always for guests.

My questions are:

1. What word/idea does the phrase "menos del comer saludable" attach to?
2. Why does the writer say "si quieres" instead of "quiere", given that s/he already chose to speak to the readers in usted form, i.e. "adaptarse" instead of "adaptarte", "está dispuesto" instead of "estás dispuesto"?
3. What does the "se" in "se está dispuesto" mean?
4. What does "claro está" mean?
5. Why is the subjunctive mood needed in "sea sin azúcar.."?

Answer 1

1. Here, del refers to proselitismo. This is, y menos hacer proselitismo del comer saludable. In your translation, don't try to convert them, and even less into health food.
2. This is the impersonal-reflexive construction. In English, you would say if one is not willing to cook. It is a third person construction, nothing to do with the use of usted.
3. Same as the previous bullet.
4. You translated this correctly; it is one of the many ways to say of course.
5. In fact, sea does not work as a verb here, but as an alternative conjunction. And you have exactly the same construction in English, using the subjunctive of the verb to be; you can translate sea as be it: [...] be it sugar-free, salt-free, alcohol-free [...]

Answer 2

I would prefer put these lines it into a comment but it was not possible due to the extension issues.

1) Se refiere a: "en especial aquel del"

2) No está hablando de Usted. Por ejemplo: "Si no se está dispuesto a..." es distinto de "Si (usted) no está dispuesto a...". Aunque por el contexto quede claro que se refiere al lector.

3) Sugiero leer este enlace.

4) Significa que es obvio. Clearly, of course etc.

5) No es "necesario", pero habría que reconstruir la oración en una forma diferente si se quiere evitarlo. Eg. ...y no pretender hacer proselitismo, especialmente de "comer saludable" como, por ejemplo, evitando el azucar, la sal...