Maybe the best approach is an integrated method.

Our only concern is a black swan / cataclysmic event that we cannot predict or have not weathered. 

I dont want to sound insensitive but it is a concern and I am hoping to get others opinions.

I am more concerned with putting myself in a position to continue to expand my portfolio.

You may want to consider liability concerns about forming an entity and the pros and cons to that.

Regardless of the fact that it likely won't be approved, it is just a bad idea if it was approved.Here are my concerns and questions: No-one ever knows if their relationship will last 30 years. and I don't want to be in a 30 year contract with a significant other.

(Note however that the notice you posted concerns violations observed in March 2017.)

Some things you can do beforehand are: research the area to understand the local demographics and whether any similar type businesses have previously been approved, whether there are any currently in operation in the proposed area, if there are - evaluate what they are doing right or what they are doing wrong (how are they similar or dissimilar to your proposed property), reach out to the neighbors and get their input and try hard to get them on your side, reach out to the police department and listen to any concerns they might have, etc. 

My biggest concern is selling these solid, cash flowing properties and then not finding that next larger property.

The Denver market seems competitive but I like the BRRR method of investing.