When dealing with retained counsel, a person has a constitutional right to counsel of his chosing. Things are different with state appointed counsel, but that's not your situation. So, in theory, you could change attorneys the day before trial.
Now, whether that is a good thing is another matter. I recommend you meet with another attorney as a consulatation, either in person, or over the phone. If you have the indictment or charging instrument, plus the police reports, that would be helpful. Ask that attorney about how they would approach such a case. Consider it a second opinion scenario. With that information in hand, you can make your own decision about the risks and rewards of changing attorneys, not to mention the increased costs.
My partner, Ed LeClaire, pracices in Washington. Feel free to give him a call.
You should probably start by addressing your concerns with the attorney you have already hired, but failing that, you can always seek out other defense attorneys and consult with them. Should you find one that you would feel better about working with, then that and you would work together to set a motion for a change in attorney with the court where your case is being heard.
Many attorneys offer free consultations and you can then decide if you want to change attorneys. The court often has the final say in whether the new attorney will be allowed to substitute in.
Concerns with your attorney should probably be addressed with your attorney first. If you have done that and the situation has not been resolved to your satisfaction, you should probable seek new counsel as fast as possible. The case may seem easy to you, and it may be. But an attorney just coming into the case will want to be very certain of the case before he or she tries it. Also, attorneys schedules generally aren't wide open to take trials, which even the fastest jury trial will take a full day. So you will need to work with that. Also, the court may be unwilling to let you change your attorney in midstream. While you have the right to an attorney of your own choosing, that right is not absolute, and the court has a lot of discretion whether to allow the subsitution if the subsitution is going to occur very near the trial date and the new attorney is seeking to move the trial date.
If you want a new attorney, get one on board as fast as possible.