I like the feature, but I think a few adjustments can benefit the game:

1. Let us rank up souls like we do champs. If I have a 4* soul on Fayne, let me create 4 other 4* "chicken souls" and upgrade Fayne's to 5* etc..

2 Maybe have the altar drop split souls if it's for an already awakened champ. I have a couple of 5* awakened champs and I keep getting 2*-3* souls for them....all I can do is sell them for next to nothing.

3. How about no souls for champs we don't have? I have a bunch of souls just sitting there: too good to sell, but useless and taking up storage until I pull the champ. 

4. Instead of selling the soul for coins, why don't we sell it for essences. I know we can buy essences with coins, but the conversion rate is just silly. The amount of leggo and epic souls I have to sell just to buy enough essences to buy a split 3* soul is insane. I don't know the exact math, but the trade off doesn't make a lot of sense.