He explains the most difficult concepts in a very simple and clear way.
You seem to have your good sides and connect to some students. You can't win them all. Everyone has a different learning style, need for audio, visuals, excersis. Try to add more variety. If it's all chalk on the whiteboard students will vote with their feet and go with the books. They rightfully consider that a waste of their time.
Who recruited this guy to this university?
Lot of work for you to move a away from your predecessors 1960ies script maybe.
You do not teach what is in the book. Plus, you ask very difficult questions in the test. What do you want to prove?
Maybe going in the same direction. People manage their time not intending to copy the whiteboard chalk and learn nothing from that. If you write fast to push the topics through students can't focus on understanding. They try to pass your exam by using the books. Forcing them to attend via exam specifics questions that come up in last lectures is really unfair and direspectful of their own time.
Having studied aviation engineering and working as self-studied IT freelance based on a part-time MBA, any student with some brains will be totally disaffected by "chalk physics" w/o meaningful exercises.
From that part-time high-speed pro lectures in the MBA I knew it can be done very differently using Power Point slides etc. to save chalk time. One easy reccomendation is hand out sample exams early for the book readers that hold up to self-teaching and passing with a good grade. Everyone will know what it's about and has no excuses for wasting a semester. Keep in mind wasting big ressources and failing when trying hard is deeply demotivating. Don't assume anyone to be a slacker. They all have their own tough choices on a hairstring budget or very judgemental parents at home. Such frustration may result in a very personal or harsh critisism. Try to find the gold in it too. Some still have to learn organizing a study or not to take up too many classes in a semester. Some may have structural limits to take the full plate scheduled offcially or retrain basics from long ago or bad teachers in their high schools. Or have a night job in a bar.
You can only improve some way every semester. No past exams on the campus black market make it hard with any first timer.
Your university should offer an assistance programme aimed to improve and reflect on your teaching. They all do today for beginners and thats safely outside of asking colleagues. Actually being open for change is a very good move from you.
Maybe you take this as goals: "making it more motivating to attend for different learning styles" and "more accessible to take home and self-study to manage their own time or catch up after not attending" and "fair to pass by clear expectations reg the exam questions" and "dish out one or two small exercises / follow up questions" be careful not to overload on these and post them online too for people who missed out.
Does your administration offer an optional excercise tutor for your course?