As I said in the Debian bug report, note that it may be extremely difficult to provide /bin/vi as something that'll consistently work in rescue mode; if you have a more feature-complete version of vim installed then that should be preferred as the /usr/bin/vi symlink, and it would be a recipe for confusion if /bin/vi and /usr/bin/vi pointed to different things. However, it may at least be possible to provide /bin/vim.tiny, which you could discover by tab-completion or similar.
As I said in the Debian bug report, note that it may be extremely difficult to provide /bin/vi as something that'll consistently work in rescue mode; if you have a more feature-complete version of vim installed then that should be preferred as the /usr/bin/vi symlink, and it would be a recipe for confusion if /bin/vi and /usr/bin/vi pointed to different things. However, it may at least be possible to provide /bin/vim.tiny, which you could discover by tab-completion or similar.