All the merged mined coins all need the same basic template from which to update themselves:
A copy of bitcoin with the merged mining patches applied.
Given that, each coin then only needs to fork it and apply their own usually pretty trivial modifications that makes them different from each other, such as their coins per block, their difficulty adjustment system, their default ports, their IRC channel or channels, their magic handshake bytes, and the cosmetics.
So really the best place to start is with a good recent stable copy of bitcoin.
Otherwise its a huge waste of programmer time with everyone hacking directly at just one coin instead of all being able to work from the common ancestor, which is bitcoin with ONLY the merged mining patches applied.
NOTE that doing it this way would also allow I0coin and geistgeld, the most troublesome / hardest to merge, to be updated too, allowing more people to be able to successfully merge the full panoply of merged mined coins.
So for anyone who is actually going to merged mine, having this raw "pure bitcoin with ONLY merged mining patches applied" is pretty much a no-brainer, allowing all merged coins to then be upgraded thus allowing all miners who merge to maximise their merges.
(To update Bytecoin you would diff it against the version of bitcoin it was forked from, then apply that diff as a patch to the "raw bitcoin with ONLY merged mining patches applied" repo, nice and simple. Oh and pick a block number at which merged mining will turn on.)
-MarkM-
Why is every single post you make, TLDR. You are smart, we get it