I wouldn't get a phone just to stem monotony, but if you really feel windows phone OS works good for you then yeah get it.
Is the iPhone monotony harming you in any way?
I hate to tell people to wait, but hopefully Nokia will get the WP movement going and with it their application ecosystem. With that, I say wait for very top of the line Nokia hardware and hopefully the app ecosystem will make some strides in catching up with iOS and Android.
I used iPhone for more than 2 years and it gets boring after a while. Android is no solution as it is pretty much the same monotonous icons. I waited along for a decent Windows Phone 7 but had to pull the trigger with Bold 9900, which is a great phone but would have definitely bought Lumia 800 if it was available that time. I am even willing to switch at no additional cost to Lumia 800 if I could.