For all commanders, the kind of starting hand you want generally includes at least three lands (two if you have a decent selection of mana rocks in your hand)
They can buff one another, deal damage to enemies based on sheer numbers, cheat each other into play, and more.
In particular, Ive tried to avoid narrow commanders if you do a bunch of X and Y, you win cards
The player gets incredible value from doubling those effects, which are common in Sultai colors, and cards like Strionic Resonator and Panharmonicon can push it to the next level
Any concerns about printing thousands of new images of angels, all of which will now become angels themselves
Even if your Gollum is destroyed or enters the graveyard for any reason, you can bring it back to your hand for a relatively small cost