The Grant/Breyfogle Batman run in Detective Comics
- very little, or none at all, has been collected. I'm not sure how "important" their run was, but it was well-received at the time and still holds up now (I've begun to collect a few of the issues). They created characters such as Scarface and the Ventriloquist, Anarky, Ratcatcher and others who have endured over the years since.
Similarly, Peter Milligan had a shorter run in Batman
and Detective Comics
, with one-off stories that could only be described as weird but wonderful. His take on Batman divided opinion but again the reaction from the fans was largely positive. His work deserves to be collected.
It seems like every Batman story is released in TPB nowadays, so I think DC should give these stories a new release - they deserve to be re-discovered.