Depending on the number of permanents 2 CMC or lower, you could be looking at 10+ extra mana for the turn that you cast it
It's nice redundancy in case anyone repeatedly destroys your commander with something like Aura Shards, my most hated Commander card
Mill never had the right support to dominate any format, and if the milling failed, the mill deck would be too far behind in the game and lose but in Commander, even with 99-card decks, mill might work with creatures like Bruvac, the Grandiloquent around
Finding the right game will ultimately come down to what aspects of a trading card game matter most to the individual.
However, this is easier said than done
This one-colourless-cost Sweets Overload move deals a pretty poor 40 damage, but it gets another 40 added every time one of your Pokmon uses Sweets Relay