Probius is too simple - additional mechanics suggestion.
For all the hype of a unique play style, playing Probius comes down to simply spamming Q and W spells at enemies like any other mid-range mage. Both his auto attack and E abilities are perhaps the worst in the game, they need to have more impact and his "builder" aspects need to be improved. This suggestion, inspired by Sheth's comments, will improve both of those aspects and add some badly needed complexity to the hero.
Passive - In addition to summoning pylons, basic attacks from Probius generate resources that are converted into minerals. Attacks against heroes generate 10 minerals, all other targets generate 2 minerals, up to a maximum of 300. Minerals are consumed to enhance abilities or construct additional structures.
A hotkey has been added in order to toggle Probius into mineral spending mode. While in this mode all abilities will consume minerals and provide additional benefits.
E - Consumes 150 minerals to warp in a Photon Cannon that is not subject to the normal ability cooldown.
D - Consumes 100 minerals to warp in a Pylon that is not subject to the normal ability cooldown. Cannot exceed maximum pylon count and will replace an existing pylon if at cap.
Z - Consumes 50 minerals to enhance Worker Rush's speed boost to persist through attacks. Still affected by slows and crowd control effects.
W - Consumes 50 minerals to enhance the next Warp Rift radius (and explosion radius) by 25%.
Q - Consumes 50 minerals to enhance the next Disruption Pulse range and width by 50%.