Everything you listed are good points using theoretical, book knowledge, but isn't the only "objective" way to evaluate the two posters to put them in front of a sample of the target audience and measure their reaction? What you're doing is applying general guidelines as if you can determine the overall quality of a design by running the design through a checklist.

For example, you dock the left for having indistinct headers with inadequate contrast. But that's actually a good thing, since the headers are useless in both posters! But only in the right example are they distracting because they followed the "good design checklist".