The major problems I have seen with scriptural interpretation are the following:
1. many passages are taken out of context with the setting
2. passages are overcomplicated or twisted to emphasize a point, when the simple and obvious interpretation is the correct one
3. a passage must be in harmony with any idioms that it contains, in other words sayings that had meanings at the time of writing that have gone out of style and no longer have the same meaning. Many of the newer translations do a much better job of correctly translating these idiomatic sayings than older versions such as the KJV
Another major problem is the one summed up in the following from How to Understand The Bible, by W. Robert Palmer, (College Press Publishing, 1995, pp. 69-70).
For a full understanding of the Bible, all passages on any subject must be studied. Truth has many sides. Each passage, though true, does not always give all the truth. And usually a passage has a particular design of presenting clearly one facet of truth or of combating some significant extreme people are susceptible to. No one should ever draw a general conclusion on any Bible subject until all passages concerning it have been collected, considered, and compared.
We think of no better illustration of this than the subject of conversion. In pointing out the steps of salvation that a sinner must take, such passages on faith as John 3:16 and Acts 16:31 have been emphasized by some. On the other hand, such verses on repentence as Luke 13:3, Acts 2:38, and Acts 17:30; on confession of faith as Matthew 10:32 and Romans 10:9,10; and on baptism as Mark 16:16, Acts 2:38, and Acts 22:16 have been put aside. Only the sum total of passages on a given subject will give complete understanding.