Modifying Lighting Circuit for New 3-Way Lights

Hello,
I'm finishing out my basement and need to sort out a 3-way switch for the landing light.

Currently at the top of the stairs there's a standard switch. I think the switch is being used to toggle basement lights on/off as well as extend power to a few more lights upstairs near the top of the stairs.

Here's a picture of what I think is happening:


Power comes in and there are two hots on the top screw, one I assume is source and the other goes to 2 lights at top of stairs. Toggling switch doesn't turn these lights on/off. The single hot on other screw goes to lights in the basement.

Does that appear to be what's happening?

Now, I want to add a switch to the bottom of the stairs and make it so that the top and bottom switches turn off 3 lights (1 landing light and 2 lights in laundry room).

Can I wire nut the two blacks from "Power from CB panel" and "2 lights in kitchen" together along with a pig tail feeding the switch and then from there, run 3-wire with ground down to my 2nd light switch at the bottom stair landing?

Also, what is the difference between these two wiring options?
Option 1: http://ift.tt/1PbqPxg
Option 5: http://ift.tt/1PbqQRP

If I want to have power come into the switch, 3-wire to the 2nd switch, and then control 3 lights with 2-wire, which one is better or is there no difference? I saw other options that had two 2-wires between lights and running 3-wire between all the lights, but my lights are already wired up with 2-wire.

Thanks,
Mike

Attached Images

 

Modifying Lighting Circuit for New 3-Way Lights