Since you work in a hospital, are there other pharmacists you have any relationship with? Perhaps the director would write you a letter. I've written many LOR for both pharmacy school admittance & residencies. I do believe written fluency is a factor since a reader's discrimination might inadvertantly be assigned to you. However, sometimes, written fluency is better than spoken, so you might ask this individual how comfortable he/she is with the task.
IMO - a good LOR for someone trying to be admitted to pharmacy school would cover degree of interest in the field, ability to get along with others in the dept & the hospital as a whole, willingness to do any task, your reliability with regard to your assigned days, shifts, etc. I've never been asked to assign a number ranking & wouldn't know how to do that. When I've written them for residencies, I speak to more actual knowledge and ability, rather than general employee behaviors.
When I have sent the LOR, it has been directly from me to the school/committee. It often is asked to be on business letterhead with business franking rather than stamps, but not always. I've been asked once to affix an official "seal" which was provided for me. From the etiquette standpoint, no, you should not ask the letter writer to read it first. If he/she offers then it is up to you.