My 3 reasons to jailbreak
For me, jailbreaking has always been about UX; I tend to shy away from the more outrageous animations and themes, while streamlining the phone. Here are my 3 reasons for jailbreaking, and a ton of tweaks that might spark your interest.
1. Reduce clutter.
Bolt: Removes the battery icon from the status bar, and places a lightning bolt there only when charging, so you don't lose your visual indicator.
Iconoclasm: Looking at a fully-loaded iPhone 5 homescreen makes me dizzy...I need some breathing room. I used to use GridLock for this, but it hasn't been updated for iOS6 yet.
Springtomize 2: Utterly loaded with features. I use it to remove "AT&T" from the status bar, and to hide Stocks/Videos/Newsstand/etc. icons.
SwipeAway: Kill all apps in the app switcher with a swipe up, individual apps with a swipe down.
NCSettings: Quick access to wifi/bluetooth/data/brightness, Android style.
PasswordPilot: Saves (encrypted) your iTunes password for app purchases, saves you time.
BiteSMS: Loaded with features. No, iPhone, I don't want to leave the app I'm in to answer a quick text. Yes, I do want to see timestamps for each message, not just for some arbitrary time period. Bonus: Shows contact pictures. Ultra bonus: I set my messages on a 2 second delay, so I can hit STOP in case I catch a typo or an autocorrect fail.
Ipsum: Swipe right and back to the left to dismiss a lockscreen notification, rather than having to unlock and open the app.
QuickClear: Hit once and done to clear notification center notifications.
LandscapeVideos: Automatically switch to landscape for videos, regardless of orientation lock. Perfect for "laying sideways in bed" mode.
3. Reduce the number of physical button presses.
Zephyr: Swipe up from the bottom edge of the screen to close an app or swipe up and hold to activate the app switcher. Very fluid, and you can disable it for any specific apps/games that it interferes with.
Activator: Add custom gestures to make your life easier. At the homescreen, I swipe right on my status bar to lock the phone. I wake my phone with the home button, so I never use the sleep button, which I think has become more awkward to reach with the iPhone 5.
Muteicon: Shows an icon when your phone is in silent mode. I use this in conjunction with an NCSettings mute toggle, so that I can ignore my silent switch.
Everyone's preference and use case is different. I merely present my own, in the hopes that somebody sees some new tweak or potential they hadn't seen before. If you have any questions, fire away. Thanks for reading!
PS - F.lux. Use it.