It's obvious Arminius wanted to focus in specifically on this form of predestination and only make scant reference to the "second and third types" in an effort to make the latter look just as "extreme" as the former.
I want to say there's an easy example from recent events that shows how someone can focus in on one aspect and then project it across a wide scope to portray the whole as extreme...even hyper-extreme...
”3. It [Predestination] has had no need of being examined or determined by any council, either general or particular, since it is contained in the scriptures clearly and expressly in so many words; and no contradiction has ever yet been offered to it by any orthodox Divine. “
In Augustine’s writing there was a great controversy on this very subject; so much so that Augustine wrote a whole book about it. This controversy wasn’t in the church but was in repudiation of Pelagian. Augustine writes in Chapter 36:
"Therefore," says the Pelagian, "He foreknew who would be holy and immaculate by the choice of free will, and on that account elected them before the foundation of the world in that same foreknowledge of His in which He foreknew that they would be such...."Blessed," says he[Paul], "be the God and Father of our Lord Jesus Christ, who hath blessed us in all spiritual blessing in the heavens in Christ; even as He hath chosen us in Himself before the foundation of the world, that we should be holy and unspotted." [Eph. 1.3.] Not, then, because we were to be so, but that we might be so. Assuredly it is certain,—assuredly it is manifest. Certainly we were to be such for the reason that He has chosen us, predestinating us to be such by His grace.
Sound familiar? It seems to me Arminius is arguing the same thing as Pelagian in regards to predestination.