Your assumption is correct.
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.
Considering that the judge ruled in favor of your lawyer's request, the chance that you will be able to show judicial misconduct is almost nonexistant (though of course I don't have all of the facts).
In an apporpirate case an appeal may be based on inneffective assistance of counsel. In such a case the burden of proof would be on you to show that the lawyer acted below the expected standard of attorneys in his area. The burden of proof would also be on you to show that the attorney's incompetence made a difference (IE that the evidence he excluded was so good that you would not have been convicted if the jury heard it).
You certainly should consult with appellate attorneys to see if someone thinks there is good cause for appeal, but I would not get my hopes up. Appeals are hard to win.
"My attorney was too inexperienced to know the value of this piece of evidence." You mean you two did not go over your case and the evidence so everyone would be on the same page about the materiality of evidence? As for the bigger question, judges are generally very pro-government in their rulings and in their sentiments, and until the voters decide they are going to elect neutral judges, then the DA's good-ole-boy network will hold sway over most judicial appointments and elections. www.kennedyforlaw.com