Sadly it's not just Apple's hardware choices that suck, it's software too. It'd take more than a 4.3" screen to make me buy one. The fact that you can't install apps from outside the app store (meaning Apple gets full control of what I install on my phone) irks me.
I think the software UI needs an update and more features. It's tired and stale. Heck I'd be happy with just new icons.
I don't have a problem with Apple only allowing App store apps on their device. From a technical stand point it makes sense and helps with troubleshooting and other things. Allowing outside sources and some of those may not be up to the standards of Apple could cause problems. You load some app and it messes with some other system file then the user goes of screaming to Apple that their phone doesn't work.
Multiply that times millions of users and you have people crying Apple stuff sucks. A closed environment is easier to trouble shoot and control problems.
Honestly I think Apple though they will never admit it allows jailsbreaks for users who do like to tinker. I think if they really wanted to they could stop it. It seems like a cat and mouse game. They may make the JB team work for it but still not close it completely.