As a new Android user that tried it, its so slow and not smooth. Appreciate WP8.1 and what you have in it. Also, Widgets are so overatted its not funny. When they went away in Windows 8, I didn't miss them at all.
If your Android phone is slow and not smooth then you bought the wrong phone. I have both the 2014 Moto X and the Nexus 5 and both phones are insanely fast and as smooth as can be. I had the Nokia Lumia 830 and compared to my Android phones it was slow, laggy, jerky, and just generally not as good. I know the Lumia isn't a high end phone like the others, but compared to a Moto G which has the same specs, it still can't keep up.
@OP- The couple of WP8 launchers that are out there look cool, but ultimately don't have anywhere close to the functionality of WP8 and its live tiles. I encourage you to try something different, and experiment with different widgets and such. Android is only a grid of icons if that's how you set it up to be.
This is my Moto X's home screen. I'm using Nova Launcher and the Chronus clock widget. It's not the best looking home screen, but it gives me all my info at a glance, and I can even scroll the widget to see more info-
Check out www.mycolorscreen.com
to see some great ideas on what you can do with Android. There are some really creative themes there.