I'm a big fan of schema, both to logically partition a database and to make it easy to assign appropriate permissions. Re: SSMS, I use the filter option all the time, and schema is one of the filter criteria.

Re: extended properties, I use them a lot also. I commit all my view, procedure, function, etc. code to Perforce and populate extended propertiy statements in the script with RCS keywords. When I deploy, RCS keywords like $File$ and $Revision$ are then in the object definitions in the database making it easy to determine later what exactly was deployed.