I tried a regular Rex saddle using a blueprint with higher armor and it will not let you put on a Dom Rex. I feel Dom Rexes are useless unless there's a better saddle with armor, for boss fights. Are you able to make 1 for engrams with higher armor or some with different armor values? And imo not easy mode crafting. Maybe matching the rex saddles materials needed for higher armor value. People will be more inclined to use them more with better saddles.

Or let us use Rex saddles.

But besides that I think it's a great mod. I love it when it let's the whole server know when one is hatched. I also like how you have to farm to make an egg.