I reckon Piddles could be a re-design and re-characterisation of Pipsy.
The name's similar, from what we've seen they look alike, and Rare did mention it was a 'character from the Rare archives'.
It all seems to fall into place if you ask me, what do you lot think?
P.S. I know BlueytheWalrus has already stated this, but no one seemed to respond to the comment. I worked out it could be Pipsy by myself, I did a search to check it wasn't already 'discovered', and only came across Bluey's words.
Plagiarism not intended