It isn't poorly written.
There are two problems that come up when people who are hostile to the things of God try to read the Bible.
The first is that the carnal man cannot understand the things of God.
The second is that they simply don't know how to read the Bible and they sit down and try to read it front to back, like a novel, or they just open up to a random page and start reading, both or which are going to lead to confusion because the Bible doesn't go in order and very few of the books are meant to be read without foundation from other portions of the Bible.
You admit that you've never read the Bible all the way through (and, by the way, "reading" the Bible is not the same as studying it for understanding), so how do you know that the parts you skipped were not a part of the foundation for the parts you say you read but did not understand?
It looks to me like the problem isn't with the Bible, but with someone who is so eager to condemn it that they're not even willing to honestly look at their own failure in studying it properly.