Lets break this down for you, I think i answered this for you today already didnt I
The advance pack
You would need to add
1 x tunze2 cable
1 x YL2-1 splitter
1 x pH expansion card
1 x pH probe
Yes you could run your MH on the 6 way digital as you state, your total load is 6.81 AMPS for the MH, the new digital bars are fitted with 200amp surge protected relays. And you can use your same stated method for your T5's but bearing in mind the MH will all switch on and off at the same time as they are on the same switched circuit same as the T5's
Level sensor -
This kit comes with all you need for level control, the kit includes
1 x FLOAT sensor
1 x Holding braket
1 x Mounting assembly (the acrylic rod assy)
It does not come with the optical sensor
Hope thats helps