Archive Performance Video - What's the best codec?

Hello all,

I do video work for a Ballet company, including filming performances and creating and maintaining the archive. Previously my workflow was to render out a master file, and then create versions from that; i.e. I'd render out a Quicktime h.264 master at a data rate of 20mbps. Then from that file I'd re-export DVDs, small size Mp4s, etc. One of the reasons I did this is that I could include my chapter markers in the Quicktime file and credit info, which was very convenient. I also keep the original video files.

Now since Apple announced they wouldn't be supporting Quicktime for Windows anymore I have been looking for an alternative master file. I've tried DNxHR and Cineform, but those file sizes are HUGE! I currently shoot with two Canon c100 Mark ii, which capture at a data rate of 24mbps, so I definitely don't need a master file at a higher bit rate than the original footage. I don't have the storage capacity to handle a gig per each minute of footage, which has roughly been the file sizes I've seen in my test exports. There is a data rate limiter in Adobe Media Encoder, but since the 2018 update, I haven't been able to use it. The info is grayed out and my previous export settings that used the data rate limiter are getting an encoding error when I export.

What am I doing wrong, if anything, when exporting in these new codecs and what do other people use as their master files when exporting?