I'm disappointed also, and came in with the same expectation.
How hard would it be to fix this UI problem in the future? I'm assuming FE is too late in development for this to happen, but could it happen in a 2nd expansion.
Maybe this is one of the things you should do a DLC poll on.
The Life/Death shards thing creates a problem for Krax, as they can end up with Life Magic Champions. Do they get benefit from death shards?
One proposed idea: Life/death shoulds become soul shards.
Ceresa keeps Death Shards, which are unique and come from corruption, which she needs to power up her death magic. She gains the ability to corrupt champions making them only able to use Death Magic as well (otherwise only wraiths have it) Wraiths would also gain the abilities to get other schools via promotion,
A future sovereign may get a life magic version of this. This is probably way too much work for FE, but I think it's an interesting idea.
One thing I do want to see in future/expanded content: 2nd sovereigns for factions.
I think I just requested everything short of a pony here.