There are plenty of artifact-centric alternate wincons like Hellkite Tyrant and Mechanized Production, but this cards much cheaper, takes opponents out directly, and has the alternate Mirrodin mode when you just need to build up your board
As your stuff dies, which is pretty common, you'll load her up with loyalty counters
Tap some creatures you control, saddle up your Mounts, and get some additional bonuses
A black version would either be more midrange with better odds of hitting land drops all the way to five perhaps even with some ramp, or it would cut much of the white top end
To get to the heart of the matter, you need to consider two things: What kind of protection do you need, and how critical is it
prevents any harm to all creatures and players until the end of that turn