I see huge problems with the current system but in the current capitalistic world we live in there has to be a way to protect money/time spent on researching things. If the results of 10 years of research can be stolen as soon as they're announced no one is going to pay for research anymore.
And while your arguments are still valid to a certain extend - it has to be evaluated against the costs of the patent system and the benefits you'll get from erasing the patent system. For example right now every startup-up is in danger of running into patent troubles unless they start pair-coding with a lawyer. People avoid looking at patents because they are scared of treble damages and people avoid coding optimal solutions trying to work around patents. Companies can block each other and managers and investors are in a constant state of risk that their coders will violate patents (mostly without even knowing it). Patents are no longer used to boost innovation, but they are used primarly as a weapon.