who hates Sandman? I mean yeah I guess there are some but generally speaking most people usually at least like it.
In general I like Gaiman's writing and him as a person but for my personal taste Sandman is not the best ever but still a must read.
I usually prefer long form storytelling over episodic ones and Sandman has both. When it does a longer story I'm captivated but often felt like the one off stories didn't really add much to the overall plot. Not that they have to and Sandman is tailored for these small detours, I just didn't care much about some random story about Marco Polo or a guy lost in a nightmare city.
But some people love those one offs so YMMV.
That said when I think of Sandman I don't think of the stories I disliked (and those are just one or two issues) I think of Season of Mists and the Kindly Ones and how I've started reading it slowly then by the end of the run I just couldn't put it down and how Gaiman incorporates every mythology ever under his own blanket but it feels natural and I love that.
Also after the Season of Mists you can start reading Lucifer from Mike Carey and please do yourself a favour and read Lucifer because it is just so DAMN GOOD!