2nd upgrade increase stats. No one buys the second upgrade since it only gives charges. Make it more like diffusal where it gives charges and increases ability.
Lvl 2 Janggo
+9 to all stats --> +12
+3 damage --> + 6
+5% ms/as --> + 6% charges + give 12%
Plus then you can use it as a Chakk ult item, which makes sense.