If you have an iPhone 3G then your hardware is over two years old, and your iOS version, if updated, is still feature limited. Maybe that's why it feels so stagnant?
Interested in seeing how the iOS-development had been, I decided to enable all the features Apple had decided to disable. Basically a quick rooting with redsn0w where I only re-enabled the official features and I didn't add any 3rd-party hackware to compensate or otherwise distort the experience.
I still feel it is stagnant, but like I said, I realize this may be a personal preference. Just thought I'd clear up any confusion regarding my ability (and inability) to use iOS-features as they are available as per today.