Without knowing your performance on case and PEI, it is quite difficult to give an honest assessment.
My general advice would be:
1.Keep the overall workload light. After 2 months of prep, there should be nothing at this stage that you could significantly improve on (given that you learned and internalized the right habits for the McKinsey case and prepared proper PEI stories that actually hit the dimensions that McKinsey is targeting).
2. Work on your perceived weaknesses in 1-2 peer case interviews, and conduct sevreral chart, math, and structuring drills + speak through your PEI stories with a few friends (check out my answer here: https://www.preplounge.com/en/consulting-forum/how-to-prepare-for-a-case-study-10480) or alternatively do one final finetuning session with a McKinsey coach.
3. The closer you get to the interview, the less you should be doing and the more focus should be on enjoyable experiences. Agree with Ian here!
All the best for your interviews!