Where to Address Issues With Bad Class Formats
TL;DR: you could write a letter to your program director. However, success may be elusive, since the situation may be constrained by forces outside of the control of you and your lecturers.



It is worth addressing. The official course evaluations are the appropriate place for this, so you have taken the right approach. However, depending on the situation at your university, it may be the case that nothing you can do will make an impact on the situation. This is because the situation may be forced upon the lecturers through circumstances beyond their and your control.

Consider the following example. I am the responsible lecturer for a data mining course at my university. Teaching is 30% of my job, with 50% dedicated to research and 20% to project management. I am teaching this course in the traditional format, which I would prefer to keep doing. Last year, 134 students followed my course, and I survived (with positive student evaluations). This year, 312 students showed up, and I am barely hanging on (with student evaluations pending). Purely trying to keep up with the barrage of student questions in my inbox is eating up all my time. If I keep the course format the way it was, there will be absolute zero time for me to fulfill the non-teaching 70% of my responsibilities.

At my university, I am forced to write a formal reply to the outcome of the official student course evaluation, explaining how I will address the comments in next year's edition of the course. Hence, these evaluations matter at least a little. However, if I decide to refer to videolectures instead of ever teaching a plenary lecture again, the following will happen. My student evaluation grade will go down. The extra time I free up by eschewing lecture preparation, I will dedicate to writing another grant proposal. If the proposal gets the funding I request, I will get tenure. If I don't get that funding but my student evaluation grade remains high, I might get tenure. My situation simply does not provide me with any incentives to keep students satisfied; in fact, if I were to keep students satisfied, I actively reduce my tenure probability.

If your lecturers have mixed responsibilities like I have, it may be the case that their job parameters are set up such that student evaluations are not relevant enough to them. If not, then your success still depends on what value your university attaches to course evaluations. No success is guaranteed.

So what can you do?


definitely keep filling out those course evaluations. This builds up to a paper trail of things being wrong in your programme at large, rather than being a problem of individual courses;
ensure that you get the education you desire. If the course doesn't provide you with the education, you should use your time at university to get it yourself. Form a study group with your friends, acquire the books or other materials to teach yourself the subject. It is of course far from ideal to have to do this yourself, but if your university does not develop your skill set, you can still develop your skill set. Acquiring this optional text book you talk about, for instance, is a good move;
if you have a set of coherent complaints, showing consistent shortcomings across multiple courses and lecturers, and these complaints are shared between a substantial number of students, bring the complaints to your program director, as a group. The program director should address problems with your program as a whole, that span beyond a single course.