If you are this worried about the heat your iPad builds up, make sure your backups are working properly, then!
Also, with most apps, Procreate included, there are alternative backup service settings you can change to backup to, like Google Drive/Photos and/or BOX or DropBox.
BOX has a free 10 GBs personal plan.
Google Drive/Photos has a free 15 GBs personal plan. Also, Google Drive/Photos has a 100 GBs plan for $1.99 U.S.D./month.
A 200 GBs for $2.99 U.S.D./month.
DropBox only has a measly 2 GBs of free storage, but can come in handy from time to time.
Both BOX and DropBox I feel cost too much for their larger data storage plans.
While I am NOT a very big Google ANYTHING fan, Google's digital data storage/data backup plans are very reasonably priced per month and I use these as my one of my main iOS device data backup services.
Best of Luck to You!