There's just too much to fit into 6 issues. The clone saga ran in 4 monthly Spider-Man titles for two-ish years, so we're looking at around 200 issues. I know there was a lot of stuff they're cutting out, but the writers were probably planning on telling the story over the course of several months before the editors made them extend it. So a 15-20 issue run isn't going to fit into six issues and still be good.
Exactly. 100% agreed. It feels rushed, too. It reads like they are doing their best to touch on every aspect of the series without fleshing out the concepts, which makes it read like a bad Cliff's Notes version written by a fan.