Yep the idea is that it is covered in picked up armor, shields, swords, etc. I found this guy in the 2e monstrous manual and the AC was the equivalent of chainmail + shield for that edition, so that is basically what I wend with.I am all about more oozes!
1) The high AC for the Ooze threw me at first. I think reading your flavor its fine for this guy as kind of the exception to the rule of ooze kind, I just wouldn't use it too often. Ridiculously low ACs and Oozes go hand in hand.
It is supposed to fit in easily in a 10x10 corridor without squeezing, I just forgot that part. I will get it added2) I think the ooze's size works against him in this example. He doesn't have the ability to move through small spaces, so unless your dungeon hallways are 20x20....this guy has no mobility outside of the one room he is in for the majority of dungeons you might put him in.
Yes, it thinks so. Since I already have some descriptive text I will add it there.3) Since this is a apparently a moving treasure pile, it would be cool to make a treasure note (something like, you will often find 1d6 x 40 gold coins or something). I liked that note on the Worm that Walks, so I think it would be a nice flavor touch to have it here.