Both LOR and LSP cost a bit of money though.
If you want to look into free offerings there is Vixen 3 (that should be ready for release this year, still in beta) and HLS.
HLS has just been out for a year but is a very capable sequencer already, and Joe Hinkle who is responsible for it...
I just used that link as an example for the model of node :) They are available in 12volt version as well I'm certain. I use 5 volt dumb rgb nodes for my minitrees and those are controlled by a Renard 48 LSD in cohort with the RGB Breakout boards, 4 minitrees per 12 channels, so a total of up to...
I would use the "square" nodes on wireframes, since I imagine they are easier to tiewrap to the frames.
These are the ones I am talking about: http://www.aliexpress.com/store/product/DC5V-input-Square-type12mm-led-string-light-RGB-color-50pcs-a-string/701799_605976057.html
Those are "almost always" 100 mm (10 cm's) between nodes.
Unless you specify otherwise in your order of course. I find that they are nice to work with, since you can shorten it without too much problem by tiewrapping each node to conduit at 5 cm's distance between nodes for arches for instance.
Nice idea!
About the only problem i see is the 0,25 inch diameter holes, that translates to 6,35 millimeters... There are no LED's I am aware of that fits that.
LED's are either 5mm, or 8mm a.f.a.i.k.
As Matt said.
But, what you REALLY should do as well is to think long and hard about what you want to accomplish with your display.
That more than AC vs DC is what suggests the type of controllers you want.
Wanna plug in standard 240 volt string, go LoR (Expensive, but easy)
Want to use...
Sure you can inject in the middle, thats what I do with my minitrees, 2 x 50ct, 5 volt rgb strings that has the connection hooked up between them so I "inject" the power in the middle of the tree instead.