I have not played the game, but I have read the rules carefully. If I had to guess, I would say that the game is about 3.3 in weight (e.g. similar in weight to say Grand Austria Hotel), a bit lighter than Signorie.
I have played it once and before kick off I was concerned that the multiple coloured workers would offer too many options and lock the game down with AP. That didn't happen. In fact the decisions seems pretty straightforward and even as new boys the game licked along very quickly. There is no real player conflict or interaction beyond getting to the telegraphs and stations first to get the bonus, so I would say that its not heavy at all. If that needs to be a number out of 5 then I'd give it a clean 2.5.