I played through your campaign, and while it has its merits, there are some notable shortcomings.

As Kyle mentioned, the outdoor segments shine the brightest in this campaign. They are visually appealing and generally enjoyable.

On the flip side, the indoor sections leave much to be desired. These areas are often uninteresting, featuring narrow corridors with minimal engagement.
Even the more unique indoor environments fail to offer anything particularly engaging even when they change the aesthetic.
This issue also extends to the outdoor sections to an extent, which do sometimes feel very "samey", though it's not as bad because the general aesthetics make them stand out a little more.

One other major concern of mine is the campaign's difficulty. For the most part, it feels too easy, especially considering the abundance of throwable items, first aid kits, and defibrillators. This surplus of resources doesn't align with the campaign's short duration, and the maps seem to end abruptly just as they start gaining real momentum.
Playing on the advanced difficulty, my team rarely faced a genuine threat, with only a single exception during an unexpected tank and horde encounter (which we managed to survive).

The finale, in particular, was underwhelming, following a standard holdout format with a rather uninspiring layout. Incorporating more props or adding breaks in the fence, as well as additional pathways for infected to access high ground, could help make the finale a little more exciting. I do like the layout, it's just a bit bland and it kind of funnels the infected into an easy conga line to dispatch. I'm also not a fan of 3+ tank encounters. I think with some reworking of the finale more than 2 tanks for the end wouldn't be particularly necessary.

The campaign does have its redeeming qualities, such as the inventive map gimmicks and great use of panic events. I really enjoyed your creativity.

In summary, despite it's flaws, "4 Sided Coin" is not a bad campaign. It stands on par with your previous work, featuring more distinct visuals and plenty of innovative concepts. However, there are areas for improvement, particularly in creating more engaging locations and fine-tuning map difficulty in terms of item distribution and length.

Overall for your 2nd campaign I think you did a good job. I look forward to seeing what else you do.