If I'm not mistaken, isn't Cuuso just for one off sets.
Wouldn't mask packs technically count as one-off sets? They'd have the same SKU as each other; the contents would just be variable.Still, I don't think this project will be successful in either gaining support or, if it comes to that, the review process. Hero Factory helmets have no real story significance save for which characters they depict, so the only people these would benefit would be MOCists. Meanwhile, I think Lego learned from the poor sales of the mask packs that supplementary sets like those aren't worth the budget for quite so many recolored parts. Plus, since the days of the mask packs, Lego has implemented a policy that states that each new element put into production (either a recolor or a new mold) has to be offset by removing one from production. I doubt they'd even have released the Bionicle Mask Packs if the theme were introduced in this day and age.
Additionally, this project is just exceptionally vague. What range of colors would the masks come in? Which masks would be used? The proposal only features a picture of various masks available on LDD, which includes both those modeled for 2.0 heads and Glatorian heads/Brain Attack heads, so consistency's out the window. And unlike the iconic, mostly primary-colored masks of the classic Bionicle mask packs, there's no rhyme or reason for the colors they've chosen apart from making sure no existing colors are used.
Now, would I be interested in recolors of Hero Factory masks released via some other method? Perhaps. But the only feasible alternative to mask packs that I can conceive of would be new figure sets, so the question is, would I prefer new figures to have new masks, or old masks in new colors? I suppose it would depend on the figure. For instance, I wouldn't necessarily object to a new Furno using one of his old masks in Silver or some other color that would complement his color scheme. But new characters often do best with an entirely new look, and sometimes a new mask mold is necessary for that. One thing's for sure, though; we're not likely to get any masks with the sheer color variety of the classic mask packs for a very long time, if ever again.