Well, they are still not developing anyone. They are trading for guys who aren't completely developed.
But they traded Strahm for a guy without options and Walker still exists, so flexibility isn't that great. The Rule 5 guy also can't be optioned of course. Johnson and Curet and Backhus can be; they will share one roster spot probably unless Walker is in the rotation and McCambley (the Rule 5 pick) doesn't make it out of camp.
Basically Duran, Keller, Alvarado, Kerkering, Banks and Bowlan are locks. That leaves one spot if Walker's the 8th, or two if he's not. If they like McCambley he will beat out all three of the guys with options probably, at least to start.