Hi,
I just discovered the power of ido.el, which makes obsolete numerous
hacks of mine.
The behavior when setting ido-use-filename-at-point to t is incomplete IMO.
For example, with the cursor on "ido" in (require 'ido),
find-file-at-point would propose the complete path to ido.el, which I
find extremely useful.
So I suggest using ffap-guesser instead of ffap-string-at-point to fix
this issue, or at least provide an option to enable that behavior.

Best regards,
Yann