As “informed consumers” we should demand this. I wish there was a list of standards (website?) as OP suggests. Many hashgochas also rely on others. For example, most Chassidishe hashgochas cannot obtain basic chemical ingredients without relying on OU or Star-K who actually have Mashgichim on the ground in China and other countries around the world.
Also, it irks me to no end that Yoshon is hardly even a back-seat issue, and requires an entire booklet with tons of research to be able to follow. Many hold it’s D’Oraisa, and just because others are lenient, it’s almost completely ignored. Agencies will put a D on a product just because the machine is not fully “kashered” between runs, yet is still clean. At the same time, they stand behind Chodosh products that many hold is Assur D’Oraisa! IMHO, that’s a massive joke!
(And no, it’s no longer the case that most grain in USA is last years or older)