You might want to consider adding support for:

1) sysname/nvarchar input

2) fully qualified names

Some good items that don't seem supported for testing:

1) item in another database

2) something with max synonym name length.

3) temp table with space in the name, or fully qualified temp table names

4) temporary stored procedure, or function

5) indexes

6) sql injection (your input is used right now as part of raw sql) eg: #a;

7) are you expecting to use this for columns?

8) drop command fallthrough - seems to run drop even if it does not exist. eg input: [some item that won't exist]

Just a few thoughts,

John