Time to Feed lets you remove creatures with flying or other types of evasion that might otherwise be a problem for your grounded monsters
Put one of them into your hand and the rest into your graveyard
The biggest thing in my mind for not ranking Izoni higher is that if you get behind on the board, and can't attack or pull creatures from your graveyard, this commander has a hard time recovering
As for the reanimator sub-theme, your commander essentially reanimates something whenever you complete a dungeon, which will be early and often
It pairs perfectly with Toxicroak, which, when combined with Nihilego, can deal 30 Poison damage each turn, leaving room for Paldean Clodsire ex to come in and sweep
Some players have cut crispin and the darks for rainbow energies and those builds will still be strong too