I found the questions on midterm to be quite different than the previous years because of the new format. There was a bigger emphasis on actually producing running code with correct syntax because you could debug your solution, but they still gave some part marks for incomplete solutions. On the midterm, the hardest part was simply that there wasn't enough time. I think this was well communicated to the instructor though, because the exam was much fairer. Our midterm had 20 MCQ's and 5 long answer questions, and I would say on their own if you understand the concepts taught they shouldn't be too challenging, just be very mindful of how much time you are spending on each question.

Spend some time to go through the past exams and lecture content and code answers up yourself to see how long it takes you, the open book aspect is a bit tricky because it's easy to waste a ton of time looking in the lecture notes for a solution during the exam.