Good on you for those before and after pics. Very nice work there.
Anytime spent here will tell you that the windshield frame under the glass is almost surely holding a few more surprises. I have changed out my windshield twice in over a decade and each time it was amazing how much rusting was going on where the sun don't shine.
In my case, I never needed any welding, whew!, but the rust was distributed in patches around the entire frame. I blame the useless rubber molding that seals out nothing and allows the cancer to proliferate.
After reading here, I took that to heart and eliminated that molding by relying upon the adhesive to seal the glass which it does, along with some added black caulk to fill and seal the edges of the glass. No moisture can get to metal frame under the glass.
The next time I need a new windshield, I am hoping this makes difference. It has to be better than what we got from MB that seals out nothing. The weep holes along the bottom edge may be helpful, but a molding that lets water in, needs a rethink, me thinks. haha Thanks to all here.
One last addition I did was painting the whole windshield area and more with a gray Herculiner truck bedliner roll-on product for what I hope is a one and done rust preventative. I too, tend to not wash my van as often as I should, but give it an occasional rinse off. In that respect, the bedliner is ideal for me.