In your particular case most probably you will be interested in the config with one big SSD aggregate attached to one controller, another big aggregate with NL-SAS drives connected to the second controller.
SSD aggr: 10 data + 1 parity + 1 hot spare
NL-SAS aggr: 2*(14 data + 3 parity) + 2 hot spare
Then apply QoS on volumes to separete hosts if needed.
Maybe, just maybe, you might be interested in taking 4 SSD from the first controller to add them to the second controller as read/write cache, but since FAS2600 systems already have read cache on board you might not need it.