Don't worry! The 2000 character limit only refers to each item of feedback - not your entire feedback. You can send as many individual pieces of feedback in the one submission as you like.
We do this to keep the feedback spreadsheets we send to the writers manageable and readable and we think 2000 characters per feedback item is about right.
We hope that you can fit your feedback into one box, but if not you can add another feedback item to the same submission and make further comments there.