I think you mean possession of less than 2 ounces, not grams.
The Court will inquire into your finances and expenses and only appoint you an attorney if you are determined to be indigent. If you can afford an attorney then you have to hire one or do without.
Its impossible to predict what will happen with your case. A reduction is highly dependent on the strength of the case and also on the policies of the DA's office in your county. Possession of marihuana is definitely one of those crimes that is viewed liberally in Texas, especially if it is your first offense. But at the same time, smaller counties tend to take cases more seriously since their caseload is much smaller.