EDIT: <---snip
EDIT2: just been doing some reading up on the SATA specs, it seems pin11 on the power connector can be used for stagered spin up or activity signal, just no idea how to use it.
Also the normal way sata activity is read is via the controller, on many sata controller cards you have a pair of pins for a combined activity signal and a pair of pins for each individual connector.
Same thing on sata multipliers (a thing like a usb hub but for sata, lets you pulg up to 5 sata drives into one port)
However these things are far to expensive for me to afford
