I love launcherpro. Yes, sense is pretty and I like it too, but there are a few reasons why I use LP.
1. Customizing the dock. You can have up to 3 docks at the bottom, in which you swipe to change. The main dock, I just have the app launcher in the middle, phone on the left, and Google voice on the right. I swipe over and my second dock has shortcuts to settings apps, like spare parts, setCPU, LTE on/off, etc. You can have up to 5 shortcuts per dock. You can't change any of the buttons at the bottom of the Sense rosie.
2. Landscape orientation. Sometimes I lay my phone in a horizontal manner using the kickstand. The homescreens rotate and everything looks great. With the stock Sense rosie, you can't do this unless your phone is docked in the car mount, or you use some of the buggy landscape rosie mods.
3. Number of homescreens. You can have as many as 7 homescreens as with Sense, but you can also have less. I prefer only 5 so I can have my fullscreen widgets for Bookmarks, Calendar, and People (all available when you have the paid version of LP). Plus, there are a number of different transitions, and the infinite looping. All very cool.
Yes, you could live with Sense and use it. But that's the great thing about Android...choice and customizability.