Given that we have decided that black is not an optimal splash color (and that Underworld Dreams costs BBB), this win condition seems suboptimal
However, in the last year, Ive seen many designers maintain singleton in the nonlands while doubling up on land cycles, emulating Andy Mangolds Bun Magic Cube
Although the deck has a reasonably low average converted mana cost (CMC), topping out at 7 CMC, hopefully you won't feel the lack of ramp so much
If Im not wrong, there are actually more Gondorian legendary creatures than there are Rohirrim, too
A perfect aspect ratio ensures design consistency and keeps cards compatible with packaging sleeves and boxes
I will definitely cut doomsday and the Omniscience + Show and Tell pair at the least and go from there