I do not understand the phrase "drop filing".
If you can show that your court appointed attorney is not performing as a competent attorney, you can ask the court for a new attorney. You have to show that the current attorney is performing below the standard of a competent criminal attorney.
The above is not intended as legal advice. The response does not constitute the creation of an attorney client relationship as this forum does not provide for a confidential communication.
You are not likely to find pro bono criminal attorney, as that is typically covered by the public defender. A lot of people mistrust their public defenders because they don't get a lot of time to communicate with their clients, but they tend to be very competent and dedicated attorneys. In the rare case that your attorney is actually not adequately representing you, you can tell the judge that you want a Marsden hearing. If the judge finds that the attorney is not doing an adequate job, the judge will appoint another attorney to represent you.