Low acceptance ratio is tormenting and confusing for many newbies, just like i say in another article"Low Acceptance Ratio". After so many experiences and failures, I have a little idea for improving acceptance ratio.
First of all, you should estimate the value of you photo just before you shoot it. That means you must take photograph more thoughtfully and carefully. So that quality of your pics can be ensured.
Selecting pics is another important step. After a hard work for shooting pictures, you might be reluctant to give up any single one of them. But you have to realize and admit that some of them will not be accepted. The correct thing what you should do is finding out these pictures and leaving them behind.
When you shoot a lots of picture in a same subject and you cannot be sure those pics will be acceped, don't upload them all at one time. You can choose several of them to upload and find out whether being accepted or not. Then you can decide to upload them all or give up them all.
I hope these advices can help you to improve your acceptance ratio even though mine is only about 45% :-)