Semaj Christon PG from Xavier is another guy I would look into drafting. Good size for PG, 6-3. Needs some work but a lot of talent. He is a guy that will go in the teens. Draft him to be the backup to Lowry if you resign him.
What about Thabo Sefolosha in FA to backup Ross? Good defense, can knock down a 3 for you when you need it.
Trade for Koufos like I stated above is something I would look into. Good backup and cheap.
Not the greatest but it keeps the core together and adds a few other young solid pieces to the roster.