Should I bother increasing the aesthetic value (landscaping, newer homes, etc) to make it feel/look more like a Mobile Home Community?

It's partially newly updated, with some areas that could use modernization but are not aesthetically unpleasing.

While it is a legal 2 unit, it needs at least 15-20k of work to get it there.Are we making a mistake putting our aesthetic and character desires in the way?

Go for safety and livability, then work on aesthetics. 

If you will be abiding by the Secretary of the Interiors Standards for Rehabilitation, or if the review board requires certain aesthetics for the home, you may need to use specific or hard to find finishings which could be more expensive.

The property was built in 1978, so it isn't the most aesthetically pleasing, but the tenants there love living there (from what it seemed like during my walk thru). 

(school, lot, area, desirability)But when it comes to aesthetics, mechanics, roof these all can be address "affordably" if numbers work.When is comes to structural, or foundation issues.... then it's depends on ###s if you can turn a profit if you fix it.

This is similar to construction methods for condos near the beach, only your area would probably necessitate higher end design/aesthetics.

Stats:fixer upA lot of aesthetically interior and exterior work needed.New BR and kitchenPaint all roomAll floorsNew doorsPaint and replace wooden shingles outsideClean up yard and brush Possibly build a new drivewayAnd more.

We are also doing some of the 'extra' aesthetic improvements to our commercial properties, now that we can get contractors to actually commit to jobs.