Learn English – “I was all but angry” vs “I was angry”

Insist is an intransitive verb. You can’t insist something or insist someone. You can only insist, and then say what it is you insist, using a clause beginning with that.

Want is a transitive verb. You can want something and even want someone. That’s why we can say I want you. That’s a complete sentence, but alone it means something rather intimate. That, however, isn’t the case when it’s followed by the plain form of the verb preceded by the particle to in your example.

It's generally regarded that the two are grammatically acceptable pronouns in American English. However, "one" is also considered to be more formal than you and excessive use of the word can lead one to appear as overly haughty or pretentious. One can use the pronoun "one" as an impersonal pronoun that's representative of the average person - this generalization can lead to a sense of social superiority.

One of them isn't really more correct than the other - however, "one" can sound rather pedantic when used in relaxed or informal settings. This is realized in the object case when "one" sounds quite odd - "When lemons are handed to one, one should make lemonade."

Sources: Grammar Girl and Capital Community College Foundation