Hi taggalucci,
Your project sounds interesting,
I did the same 1 year and a half ago, a 16x module with 637nm single mode diodes.
I stacked the beams like you, for each polarization : 2 row by 4 columns
But for stability purpose, I installed 2 big TEC under the whole aluminium assembly (also easier to install).
Here are some pics, that might help you :
Picture of the inside, you'll notice that the wave plate and one diode were removed
Attachment 36902
Picture of the module. So I believe that you'll ask me : "the inertia of the module looks big". Yes, and this is what I was looking for :p.
Attachment 36901
All in all, this is the best configuration available for 16 diodes. 3*3 configuration (doing 18 diodes with H+V polarization) is too big to fit 5mm galvo...
You will see that there isn't telescope, as it isn't necessary.