A much stronger argument against patents, which the OP only touched upon, is the existence of FOSS. Patents exist to encourage the disclosure of ideas but FOSS

A much stronger argument against patents, which the OP only touched upon, is the existence of FOSS. Patents exist to encourage the disclosure of ideas but FOSS already provides an excellent mechanism for this. Not only that, but the existence of software patents is damaging to the FOSS community which generally cannot afford to navigate the idea minefield. Software patents don't even require disclosing enough information to actually implement the idea so in many cases there is zero benefit to society. Judges also need to be made aware just how much of the modern information age is built upon FOSS.