Tri-copter build, couple questions....

[Beemerider]

I'm finally getting around to scratch building a tri-copter. For the most part I think I have the necessary components. Back last summer I bought the i86 multi-rotor control board from HK. It's about $22 and supposedly has I think up to 8 possible rotor configurations.

A week ago a local heli flier had just completed a quad using the HK KK2.0 Multi-rotor LCD board (about $30) and he was really singing it's praises.
That particular board wasn't available when I bought the other one. I went ahead and ordered it. I had originally another plan for the i86 board so I don't feel like I've bought something I'll never use. My first question is this: Is my first controller board (i86) a good enough choice for a 1st multi-rotor build (tri-copter)? Can I safely assume that the controller board needs to occupy the center point or position on the frame at least for the sake of the gyro's?

Next question--I'm using 3 identical motors (750kv) and 3 identical esc's(30amp). I've seen some simple designs using a standard servo for the yaw axis control. In setting up prop rotation and numbering the yaw adjustable motor #1, should #2 and #3 be counter rotating to cancel out the torque forces?

I'm still thinking about props so I'd welcome advice there as well. I also bought a small board that makes a common input for power to all 3 esc's.

I'm a newbie and I move somewhat slowly--but I very much appreciate and value any good advice you folks may offer. I'm sure I'll have other questions. My rememberer doesn't remember well these days!