From vertigo i would recommend:
Sandman by Neil Gaiman, it can be a heavy read at times but is absolutely
brilliant.
Fables by bill willingham, still running but you can get them in both hardcovers and trades. There are spin off series such as fairest but if they sound interesting, start with the original serie.
Sweet tooth by jeff lemire, very dark but interesting. A finished series consisting of 6 trades.
Transmetropolitan by warren ellis
Scalped by jason aaron
The losers by diggle is only two trades. There is a film as well but not the best.
Books of magic by neil gaiman
Preacher by garth ennis
American vampire by scott snyder
V for vendetta by alan moore
From the publisher archaia, i would recommend the killer. It is 4 hardcovers. By jacamon and matz
From image, there is severed if you like horror, it is only one hardcover by scott snyder and green wake, two trades, by kurtis wiebe. The art is amazing, by one of my favourite comic book artists riley rossmo. They also did rebel blood which is good as well.
I like blacksad and grandville from dark horse. They are sort of similar. Both are detective stories but with animals instead of humans. Great art in both and it works.
The first sin city books by frank miller are also good. There are 7 in total. They fall in quality the further you get along though.
Alternative superhero series:
Top ten by alan moore
Watchmen by alan moore
Planetary by warren ellis
The new frontier
Most of these are short, finished series or stand alone comics.
Also gotham central is a detective story set in gotham of course where the main characters are detectives in the gotham police force. Batman only appears once or twice. It is 4 hardcovers. They are very good.
I dont know when to stop

we have also effectively hijacked this thread.
I apologise.