After some deliberation I have settled on which armies I will be keeping/expanding and which ones are going to get the boot. As I write up lists, build and paint models, and foster its growth, I'll be linking them back to here so anybody who wants to can find them all in one place. This is part e-peen stroking to show everybody how cool I am, part show and tell so people can see the final product of my thought processes and experience, but mostly motivation for myself to finally get an army finished and not just have stuff collecting dust.
So, for 40k we have:
Dark Angels/Deathwing/Ravenwing/Green Marines
And for Fantasy:
Dark Elves/Lizardmen (depends on how 8th ed turns out really)
So, keep watching this space as I update things.