To start, I want to say the game looks great and I am excited to grind it out.

To the point, I feel that Shrooms role as a medic could be more enticing. Shrooms passive slot - 'Wincence', feels like a cop out. Healing and Support being an integral part of the Heroes kit, does it not seem that, for the hero to build 'soul' stacks as the Passive is more of a wasted opportunity and oversight.

My main issue is that for a healing character to work as intended it had been decided that instead of this hero gaining a Passive ability to help themselves or the team, the passive slot is instead used to enable Shrooms primary role. Negating the Hero having an alternate and beneficial Passive ability for the dungeons and not something that solely 'enables' Shroom to function as intended.

In my eyes, the solution to this probably could be fixed as so.
Have 'Wincence" work as its meant to, but attach the effect onto the Special Ability, so then 'Soul Patch" will read both - "can heal allies AND increases soul stock per kill"
This now freeing up the Passive Skill slot to allow for something more vital and advantageous.

My suggestions for an alternate passive would include:
a) Temporary MS buff on kill
b) Hero regen whilst static
c) Spawns twin shoulder-mounted M134 six-barrel rotary 7.62×51mm NATO machine guns

Best Regards

Exactly giving Shroom a buff would not hurt anything; I love to see his ultimate Poison all enemies in range. If they add toxic gas back in on harder difficulty’s his passive should also include not taking damage from poison cloud and not being slowed.