It's entirely possible (albeit seemingly unlikely) that humans even tend towards tiling the galaxy with paperclips in particular.

Compared to the Vast space of minds in general, they certainly do. Few minds in that Vast space have heard of the concept of a paperclip, after all.

Indeed, it seems likely. Many humans have the concept that 'locked' values are better than 'wishy-washy' ones; few have the concept of local maximums and even fewer the understanding of complex, changing human value systems. Thus a priori we should expect there is some bias or leaning in that direction, which would presumably have a chance of affecting one human in particular. This chance is greater than that of an AI's, who chooses at random.

Harry is aware of these ideas, but he often catches himself in errors. When it comes to self-modification there are no opportunities to catch your errors; you are stuck with them and will never even realise there are any.

I wonder if Quirrell realises Harry desires to be an actual god, and not just Supreme Emperor of the magical world.