I also use Nova (Prime). My tab is on ICS.
I found Nova to be very fast and smooth.
Last night I got an update available notice for it, and it's even faster now than it was before.
Runs like a rocket.
Highly recommended.
ETA: I tried GO, and most of the others, but kept coming back to Nova.
Don't know if there's an iPhone theme for it.
There are free themes available for Nova and the others.
I use one called "Gloss Blue". It puts the original app icon on a blue background. Gives a nice
neat uniform look to the icons. He has some other colors also.
Search the Play Store for something like "GO Launcher themes", or whatever launcher you're
interested it.
Some themes work with multiple launchers.