I believe there are solutions for the problems you are facing.
First of all if your comparing the Lumia 930's camera to that of iPhone 5S's camera, opt for 4:3 to get 19 Megapixel images. iPhone also uses 4:3.
Furthermore if you want to upload high resolution images to OneDrive, you have to switch to the 5 + 19 MP JPEG.
Then you must go to settings > applications > photos+camera > Auto-Upload > OneDrive.
After your there enable Auto upload and set image quality to high(as I've done in the below photo).
http://img.tapatalk.com/d/14/07/12/vehezese.png
There is another way if you want to completely remove the 5 MP JPEGs. Download an app called 1shot by Invoke IT Limited, it allows you take one uncompressed 19 Megapixel image that you are free to edit or share, the 1shot app also has continuous focus so it will snap photos much faster.
If you still have any issues, please do not hesitate to ask me for help regarding any issues you face.
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