I just ordered two 11U68 Xpresso boards (OM13058), they have Arduino headers so would be suitable for a port. But while there I noticed that the "LPC800 / LPC812 MAX Board" has Arduino headers as well.
And there's the Arch board as well, that's 3 CPUs at least, plus I already have code for the 1227, and it looks like there are other Xpresso boards with Arduino headers, the LPC1549 for example
So far we're talking about maybe 3-5 CPUs, does anybody know if the peripherals are the same? Or does that mean 3-5 separate cores?
As for the Git stuff the "Organisation" sounds ok but as mentioned I have no idea about this stuff.
IF anything is going to happen though some organisation is required and also some deep thought to try and make a platform that can be used with all LPCs, or at least a good cross section of the models.
FWIW here's a link to my Git repo
I know almost nothing about Git except that it's totally unintelligible, it's a miracle I got those files up at all 
My code has a LOT of stuff for error handling etc. For example every "thing" is an object (well it's C so a structure) with guard bytes at each end and a type byte, all functions that use that object test those bytes.
This is way over the top for the average Arduino project and too heavy for the 800 (about 26k last I looked I think, but that includes a LOT of code for strings etc that is non core). But my goal at the time was to make a framework that was more industrial strength.
Note that there are a lot of debugging calls to toggle pins (pin14high(); for example), ignore them.
Rob