The doc would say the pharmacist is not being restrictive enough because the doc has to wade through so many permutations of what is medically the same med, or has to sift through medication forms that he/she has no use for.
From the pharmacist's perspective I want a _complete_ database so I can record with very granular accuracy what the order was. Also, the pharmacy database has things like ingredients in it which it factors into allergy and interaction checking.
I agree with your other points, though. Free text entry is faster - especially if you have voice recognition.
The way to design med lookups, in my opinion, is to have a dropdown for the pharmaceutical substance the physician wants, then the dose, then an optional drop-down for the form (tab, injection, suppository, whatever).
A suitable medication form would need to be found between what's medically indicated, what the pharmacist is okay with, and what the hospital has in stock - ideally in a dispensing machine at the point of care.