Many students' concerns are based on legitimate issues that can be dealt with if brought forward in a timely manner. When they are not brought forward, they lead to frustrations that can lead to problems. If you wait to the end of the semester to complain, no one will be able to help you. At the end of each semester students will have an opportunity to evaluate the course. Comments, pro or con, can be more helpful if you reference specific things or events as examples.
Professors are in a precarious position with respect to student evaluations.
They are evaluated by students they may have had to fail, who may bitterly resent the experience, and are relatively young and uneducated in that field. When you evaluate this course, please be specific and site examples of what you are commenting on. That will be very helpful.