Statistically speaking, if you’ve already spent X time with the account you’re playing, in 3X time you’ll have much more standard runes distribution, which includes couple of Vexes or at least Guls to cube. Zod on the other hand will be hard to come by and I would spend it just on BiS item like BotD War Pike for Travi merc or fun item like eth Stormlash. BotD Archon is great if you play fury Druid with sound, but eDeath decapitator/glorious axe is BiS and is much cheaper.
For Cham you have plenty of uses now- Gulli/Shako for Zerker, Plague for Merc/Trapsin, Metamorphosis for fury Druid or even HoJ/Pride/Doom.