I have noticed this as well, and yes sometimes I do have HUGE transfers in one go. But you should look into downloading JDownloader2
https://jdownloader.org/jdownloader2
It's freeware. Basically it's like a good ole download app from back in the day, but you can select the mega nz option under the add on or optional tab and it will automatically help with the downloads by changing the ip. You don't have to sign up for anything or sign in either. Just drag and drop the mega link onto the link grabber and then hit the start downloads button. I used it the other day for about 50ish links (non-Daz products) that someone provided me and it was able to download everything even after it hit the quota.