Using S Voice might be part of the problem. I just use the microphone key on the keyboard for voice to text. Which I think is more of Google voice. Works great for me. Agreed that S Voice still needs work, but has come a long way.
Btw: you do know the stock Samsung keyboard has emoticons built in. You long press on the microphone key. I think this is great and so many other android peeps have been jealous. And like previous posters stated, there are other keyboards out there. I actually use "quick keyboard switch" to use/flip between stock/swype/swiftkey/slideit keyboards. That way I have a cool tool without going into the settings to switch.
On another note, at first I thought the camera stunk too. But I really played with the settings. Unchecked the smart stabilization and only use flash when you really need it. I also use Camera Zoom Fx a lot. It really does produce/aid in better pics with the Note 3.
In the end, to each their own. Everyone can sit here until they're blue in the face, to convince you to keep the Note 3. Only you can decide. But if you're making the jump to the S4, please understand it's basically the same camera and hardware. Just a smaller size phone with no spen. You might not be happy with it. Another big down fall, it's only 16GB and the operating system uses a big chunk of it. I know a valid common complaint of this in other forums & reviews on S4. Not much room left over. Yes, you have the external sd card, but only so much can be transferred over (besides the basic photos/music/etc).
Android is very customizable/changeable. Apple is very intuitive, as stable and standard.
I really do think you should consider going back to Apple.
Good luck with whatever you decide.
Palm Treo line > BlackBerry line > Samsung Galaxy S line > NOW the awesome & powerful Samsung Galaxy Note 3!