The Mother of Machines is going to hurt us if we damage its controller, but like Heliod, its in the transformed guise, as a Saga, will she do some damage
In terms of splashes: we now need Blue on turn one for our enablers, but also sometimes black if we want to cast Darkblast or discard spells from the sideboard, or white if Portable Hole is needed
And thats before the equipment and combat tricks come down
No, the most broken thing to do with Menagerie is to go get two- and three-drops
Starting, out we have Fiery Inscription, which is basically a Guttersnipe stapled to an enchantment
Once we are Blasphemous Acting, we might want to try Boros Reckoner, possibly with a Harvest Pyre element