Sorry to inform you, as an attorney myself, your thinking, although in line of what I personally believe, it not how the system works.
Of course innocent people should not be wiped out financially.
Would you agree however, that the taxpayers should have paid for OJ's lawyers? How about is Scott Peterson were aquitted?
The bottom line is that the state does not pay for your lawyer if you can afford one yourself. Additionally, there are many cases that are not clear cut instances of abuse on the part of the DA.
Decisions in these matters should not be decided in the light of a single case. That is a dangerous way to approach such issues. We would not want to governed by the precident set in "mob" rule, would we?
As for O.J., first there should have been a mistrial based on the jury behavior. That aside, he was found innocent, correct? I personally think he is guilty and that this trial was a travesty. But, innocent as he was found to be, yes, his legal fees should have been reimbursed, albeit with a qualification. There should be a set fee, an amount that represents a reasonable level of attorney expense.
Also, I must say I find it odd that you, as an attorney, would think that public perception about the correctness of a verdict in which the person was found innocent would in some way come into play in consideration of legal principal.