Testimony from police officers about their observations of the operation of the defendant's vehicle before the stop and of the defendant at the scene and during subsequent processing is normally very important in establishing the underlying charges. Your question indicates no blood alcohol present but blood test results are pending. The results of the blood analysis will also be very important as they may show the presence of a controlled substance or prescription medication. If you have been charged or expect that that is likely coming, I highly recommend that you start interviewing candidates for the job of representing you without delay.
Additional informs is needed to accurately and completely answer your question. However, the officer's observation could weigh heavenly depending on their training, their execution of that training and ability to testify. Wouldn't be a bad idea to set up a confidential consultation with an attorney.