You should buy EZd2 if you need these features, Toontrack have not released anything indicating SD will be updated to version 3 soon, it could still be a little while.
You can always buy EZd2 used as a license transfer from Ebay or on KVR audio forum. And you can transfer the license to someone else if TT upgrade to SD3 in the near future.
There are benefits to having both, EZD2 is lighter on resources, so it's good for tracking at a very low latency.