You are fighting your own best interests.
Roundup ready has reduced harmful pesticide application by millions of tons.
Yes, zero pesticide is best, but you can't reach the moon in one step. It takes incremental change. Glyphosate replaces much more harmful pesticides like atrazine, and we are all the better for it.
>especially patenting life,
You can't patent natural genetic sequences.
>and secondarily turning all farmers (people who work the land) into serfs
Contracts are willingly signed, and those that don't sign are successful in other areas of agriculture (see organic farming).
>I reject the pro-GMO arguments about increasing yield.
No GMO plant has ever directly tried to increase yield. Rather they mitigate risk from weather or pests.
>Lastly if Monsanto (and Big Ag) is for it, I'm against it.
I'm glad you're willing to approach this topic reasonably, and with an open mind.