Speculating about the potential usefulness (or, in Flip Murray's case, the potential harm) of the Hawks' free agent additions...
In descending order of assumed playing time...
The Hawks needed to add a couple of nice bench players before they magically made Josh Childress disappear so I think the AJC (or AJC.com) headline writer: Hawks fill Childress' void by signing Evans is being overly optimistic. Evans is four years older than Childress plus he has never played as much as Childress nor as efficiently offensively. Still, rare among his new teammates, he can make the three-point shot and he has a reputation as a good defender (Though Orlando gave up 5.3 more points per 100 possessions when Evans was on the floor last year, his defensive on/off numbers from previous years would suggest he's average at worst.)
I expect Murray to play both guard positions (badly), embodying the inverse of Josh Childress (Murray dominates the ball and scores only by taking lots of low-percentage shots.) on a nightly basis, and providing Josh Smith with some healthy competition for hoisting the most cringe-inducing three-point attempts.
Murray's managed to attempt 616 three-pointers over 332 career games despite making just 27.9% of those attempts. For his career, he scores 15 points per 36 minutes but needs 14 field goal and 3.8 free throw attempts to get those points. He has been more willing to pass the ball recently, having raised his assist rate to something resembling a point guard's the last two years. I'm skeptical that he'll maintain that rate as he transitions from playing with his Piston teammates in Flip Saunders' offense to playing with his Hawk teammates in Mike Woodson's "offense," but he did deign to pick up some assists during his time with the Pacers last year.
It's not the most difficult task a man has had to complete, but credit to Rick Sund for acquiring a backup center more capable of playing basketball well than Solomon Jones.
Morris, as you may recall, entered the draft after his sophomore season at Kentucky, was not drafted, returned to Kentucky for his junior season, upon the completion of which he signed as a free agent with the New York Knicks in a rare example of Isiah Thomas taking a chance on getting value for money. That didn't come to pass as Thomas only gave him (or Morris only earned) 225 minutes in 23 games over the season-plus he was in New York. He was not productive in his brief playing time.
Given the opportunity, he could go replace some of Josh Childress's offensive rebounding contribution. Though undersized (6-7, 220) even as a collegiate post player, Hunter grabbed 15.7% of possible offensive rebounds on Ohio State's 2007 NCAA Runner-up team and 11.2% of possible offensive rebounds on Ohio State's 2008 NIT Championship team.
Hunter should be capable of backing up Josh Smith on nights when the opposing team does not make it necessary for Al Horford to play the 4 much, if at all. Even better, unlike recent, previous iterations of energy guys (Shelden Williams, Lorenzen Wright, Solomon Jones, Esteban Batista) on the Hawks' bench, Hunter both comes at relatively little cost and provides actual energy rather than plodding and/or awkwardness.
Thomas Gardner could fill Salim Stoudamire's (shooting) shoes, but, unlike Stoudamire, there's no reason to expect Gardner to make many shots. Disappointment pre-empted, I guess. Gardner's much bigger than Stoudamire but unless he added some skills while playing in Belgium, he's no better a defender. Still, he is probably a better basketball player than Mario West and could very well make the team.