What would help sales of manga is making more of it available in an open digital format. Physical manga takes up a lot of space given its entertainment value/time to read. The larger format, superior contrast to standard pulp paper, and higher portability (without a proprietary "reader" application or constant internet connection to read on a website) makes the scannlator's "product" superior.
I recently contributed to a Kickstarter for a certain manga title that has had trouble getting an official English release because it has met some controversy in the West. I'm getting a digital edition. I already have a fully scannlated copy of the original work, so the almost $100 I spent to get this officially-licensed translation wasn't really needed. What's more, the official licensee hired the original scannlator to handle the localization -- so the old argument about "inferior fan translation vs. professional" is bupkis. I'm buying a "version 2" of the same guy's work.
What made me contribute was 1) I could get it digital 2) It's an open format (no DRM). The title uses stenography or some other watermarking to tie my personal copy to my purchase in case I should share it. I can use any normal comic reader app to view it.
This unfortunately is a minority of English-language manga release. Most require online web-viewing or only come in dead-tree edition.