Other people use the FGDE to spray on plants to eliminate unwanted critters.

It used to be a huge, unwanted field.

The house comes some unwanted extras - tenants who do not pay and live in what I consider nasty conditions (linoleum floors ripped, dirt, grime, dank air).

Switching lenders after we get a propertyunder contract is an unwanted additional step.

You should study up on the law of attraction to learn how to stop these unwanted events from manifesting in your reality.  

Preferred and common shares seems could be used, transferred with unanimous consent would prevent stock transfers to unwanted stockholders, this can be done in an LLC with members, but not sure of the tax issues, if any, with transfer restrictions in a C corp. ?

Carefull here as you could impose unwanted taxes on yourself.

This is probably good for the economy because it is helping banks get rid of unwanted properties... but what will that do to my properties.

So while yes, they may not be able to ORDER them to pay, a little unwanted attention from higher ups tend to get those bills paid quick. 

If color bothers them that much then maybe it's a simple way to filter out unwanted tenants.