Rift Build Probius

Despite being a specialist, Probius wants to at least start the game with his team instead of solo laning to get stacks for  Warp Resonance . If this is just the mid fight then so be it. If you have a displacement hero on you team like Garrosh, Stitche, or Junkrat, let them pull someone into your team then place your rifts in front of the other enemy heroes who will inevitably run forward to save their ally. This will give you a few stacks and soften up them up for possible kills.

When you get into laning, be very careful with your positioning. Probius has a very small health pool and most ganks are likely to be successful.  Turbo Charged  can be helpful for this for both the lower cooldown on Worker Rush but especially the bonus 10% move speed in pylon aura. It lets you weave in and out for placing rifts much more safely. If the enemy solo laner is playing in your wave like a Sonya or Malthael, put your turret in range of your wave but not the enemy wave. This will cause it to only hit the enemy hero. Alternatively, if the enemy hero is being aggressive on you, place the turret down on top of them and slow their pursuit with rifts, blowing them up if they stand in them. The turret targets whatever unit is closest to it when it activates and making sure it's your opposing laner can deal good damage.

Your level 7 talent is wholly determined by what you took at 1 but rift build is definitely the best.

Personally, I believe  Null Gate  to be the better ultimate. It can be used for both engaging and disengaging and is very affective at doing so. However, this is only true when the other team does not have movement abilities, like Tracer's Blink and Recall, Genji's Swift Strike and Cyber Agility, Illidan's Sweeping Strike, etc. If the enemy team has too much mobility to justify  Null Gate , just take  Pylon Overcharge .

For pylon auras, I find  Power Overflowing  and  Shield Battery  to be very interchangeable. The former good if you have an additional mage and the latter for if the enemy team has sustained damage like Lunara or Gul'dan.

16 is another situational tier.  Quantum Entanglement  is the typical pick, especially if you took  Null Gate , since it makes  Gravity Well  redundant.  Interference  can also be good if they have a lot of magic damage. The only talent I wouldn't take on this tier is  [Repulsor]*  since it ruins both multi rift bombs and  Null Gate .

Shoot 'Em Up  is typically what I take at 20 since it's just more damage and a structure will always get hit by all the procs assuming the rift is in the structure.  Gate Keeper  can also be a good pickup if the map has a lot of narrow cutoffs like infernal Shrines.