My feedback for Sick Day:
What your game does well:
The game makes use of tower-defense elements to execute the theme in a fun way.
The controls are easy to learn, and the UI gives the player all the necessary information they need in order to make strategic placements of the white blood cells.
What your game doesn't do well:
It might just be me, but the game struggles with balance and variety. I got really far with just using the 35-cost gunners. I also didn't understand the brawl cell if it can't move past the bounds of the mitochondrion.
Although the pathogens look different, they are pretty much the same enemy with varying health.
Areas of Opportunity:
I would find ways to give the player a more compelling reason to place down other units. Perhaps you could make it so that different white blood cells can deal more damage to certain pathogens?
I hope this feedback helps!