I just doubled my pledge ($60 reward to $120 reward). It's all I can afford. I don't know what else I can do other than get the word out there and promote it.
Unfortunately, the kickstarter is slowing down. It's too be expected, as more or less everyone who wanted Shenmue 3 and would have pledged, did so on the day the campaign launched. That's just how it works. More casual fans and those who haven't played the series (but might be curious), would be more reluctant about backing a kickstarter. Unfortunately, I don't think the cynical (and almost negative) press has helped at all! It's really quite infuriating, as it's created this idea amongst the general public that the kickstarter campaign is just a PR stunt and a way of gauging interest and that Sony and other investors will actually be footing the bill. This is obviously not true and funding is needed from the kickstarter.
Hopefully, by offering some new reward tiers, it will boost interest and offer an incentive to those who have already pledged, to up their pledge.