I think it would be a very good approach that does not necessarily buff Karax, but provide him solutions to many mutations and, of course, add a lot of fun. Also Karax cannot sell his towers like Swann, while he has no transport units to carry his workers around (like crossing terrains and to strategic points). Warp prisms can help narrow this gap.
It might be useless in most occasions, but adding it just won’t hurt.
His probes should get longer range and a blink.
That would encourage players for more aggressive Cannon Play. Karax’s Probes as it is now is so weak that you need to be a super Karax pro to play cannon play
True. I think adding warp prism is sort of a “orthodox” buff to that weakness.
No matter how much you ask, new units won’t be added to existing commanders. It was confirmed by Blizzard.
Don’t give him a Warp Prism. Give him a Shuttle instead!
Yeah, unfortunately it won’t happen. No new unit would be added for very good and clear reasons. It’ll be a gong show if 1 exception is made, lmao.
That’s too bad… Zagara could use one more unit. She is the commander with least units.
And give it the ability to “suicidal dive”. Deal damage equal mineral + gas cost of the Shuttle and all unit it carries to all enemies in 2 radius. 
Haha, I know this is a joke but that would be so OP, thinking more about it.
Carrying even 4 zealot would cost approximately 520 resources, then add the assumed 200 war prism cost), dealing closer to 750damage. Essentially Protoss Nukes 
What if you have warp prism build with range, like how it can pick up from range?
Similar to Mengsk and his building mechanics: troopers can build attacking structures while laborers can build all structures. Have probes build all structures and warp prism only build cannon, battery, pylon and monolith when in phase mode.
Even if you didn’t give it ranged build, the extra health and mobility compared to a probe could make building forward bases much more intuitive.
YES
I want to doom drop with Karax
I haven’t needed to load units for transport and do drops with them for ANY commander, let alone Karax. I’m just not sure if this is really needed.
Zeratul calldown is even cheaper 
and the Karax nuke has very small area. It won’t be an issue
You mean a blink like prism pickup range?
But seriously, that would be the main benefit of a prism for Karax: immortal and probe drops.
No no. Make warp prism be able to build cannons
No. Make Observer to do that instead.
Cloaked flying probe! 
No no no, you all have to think outside of the box.
Think flying cloaked Nexus, bam!
I mean who said only CC gets to fly? Why can’t a Nexus fly and cloak, woolooloo 