Gear advice for new hiking group

Hello! Another couple and my wife and I would like to do the socal-6-pack but we're all relatively new to hiking. We're all in good shape and have done some short 5-6 mile hikes before. I currently carry an REI lookout 50 pack, with internal support and waist straps. Inside I carry the following:

• two rain coats
• first-aid kit (walgreens)
• magnesium firestarter
• a knife
• drier lint in a ziplock bag (for kindling)
• cotton balls dipped in vaseline (for kindling)
• signaling mirror
• rope
• flash light
• a platypus 70oz hydration bladder
• 2 nalgene bottles with extra water
• a suunto M-3DL compass
• marmot precip jacket for me and my wife (either in bag or on us)

I also carry a pocket knife and watch on me. My question(s) is(are) (finally!) what should I ask the other people to carry? Do they each need to carry their own survival/first-aid supplies/water? This would be tough for the girls but my friend and I could manage. Also, am I missing something? I want to purchase the following eventually, but is something absolutely required before we begin?

• good hiking boots (ankle support is important to us!)
• base layer shirt
• base layer underwear
• wool socks
• hat
• trekking poles

Ive seen your great gear page where you list what you used on the JMT trail, and plan to eventually (slowly) invest in stuff. I just want to make sure we have what we need to begin! Thanks for the help and the great blog!