Yeah, the Suns made it to the Finals without Saric even playing well. The backup center and power forward positions need to be fixed but it's not like the Suns need to add stars.
No, but they DO need to add serviceable players there. We saw in the NBA Finals how the roster as it currently stands can be downright exploited by any team with size up front.
That being said, if the reports are true, Dieng at the BAE is a good start. Add another serviceable big with the MLE, and fill out the roster as needed, and I think we would be good to go.