Weblate just got new feature, which might help you attracting new translators - embeddable widgets. You can put them to your website to show current state of the translation and attract new ones to simple introduction page.
Right now, there is only one widget, but I hope to add more in future. However I'm far from being good in graphics, so if anybody could come up with some templates, I'd gladly use them :-).
Anyway the current widget for Weblate itself looks like this:
