Firstly, thank you very much for the shout. :)

My thoughts on the films:

Planet of the Apes - Completely agreed. An iconic masterpiece.

Beneath the Planet of the Apes - I liked this a lot more than you, though it is still a bit of a mess and makes no sense. But the sheer weirdness of it - the mutants, the people worshipping the bomb, etc - makes it an enjoyable watch with the right mindset.

Escape from the Planet of the Apes - Hugely enjoyable and ridiculous.

Conquest of the Planet of the Apes - Works well, but the limited budget causes a few problems, and this is when I started to notice the ape make-up gets gradually worse throughout the sequels. In my Blu Ray box set, I also have the rarely seen original version alongside the regular cut, which features all the violence restored that was edited out at the time, along with the original, darker ending (essentially the same footage was used in the released version, but recut and redubbed to make it less bleak).

Battle for the Planet of the Apes - Easily the least of the five, but still worth a look.

Great article, by the way. :)