I know you are talking about an ESL class.
It depends whether that ESL class occurs in the student's learner country or in an English speaking country.
In the former case, I think an ideal ESL class is the one who gives the student the opportunity to forget his native language and only hear and speak English, with the teachers and mates. It should take place in a comfortable place and provide pleasant situations to the student. He should feel it as in his "second home in a foreign country".
In the latter case, since the student is already experiencing real English outside the course, I think the ideal ESL class should be highly focused in advanced grammar use, students experience share. The class should be carefully previous planned, generally these are quick courses and the students are in a hurry.
Finally a good standard ESL course, in my opinion, should be long, without hurry, and the least demanding possible. It should not rely only on the time the student has to do homework and selfstudies. Usually the students have another important activities, regarding their lives, jobs, studies, etc. If they pay for an ESL course, they want to be taught the most softer possible way, that is, with the minimun effort, learning without even taking notice of it.