Just got the OK from Travis Nichols, so yeah, I'll add Heckadeck icons in the future.
It'll probably be the update after next—since I can't use my font design app until the license money comes in, the first upgrade will mostly be things that don't need me to draw any new symbols. After that will probably be a cards-focused update (including Heckadeck), then a dice-focused update, then things get a bit hazier.