The back-up options would be Vial Smasher the Fierce as the ally option, with Kydele, Chosen of Kruphix and Thrasios, Triton Hero
You can probably see where this is going With both out on the battlefield, these two cards form a neat infinite combo that lets you draw through your entire deck
I first built this list purely because I wanted a mono-blue control deck, but I was surprised at how consistently it won on turn 3 or 4
This lets you activate tap abilities including those that produce colorless mana the same turn creatures enter the field
As well, leaning heavier into the lower converted mana cost creatures will help this deck go wide and be able to keep churning through both your opponent's libraries and your own
Whenever I set up a lock (where you have permanents in play that allow you to gain 2 life a turn, meaning your opponent can never draw again