If you're going to make it, I'll be happy. 
I will If someone who knows how managing entities works

But I don't understand one thing: do you want multiple default base spots, from which one would be picked at random (as in Gloom, I think), saving of blueprints for base(es) at your computer, saving the blueprints server-side by admins or what?
all of this

And one more thing: while you apparenly figured out a way of technically managing them, how would they load? Server side mod, or is it going too deep for it?
First part of my post is basically vcxzet idea rephraset for the masses

The second one came to me when I sat for a while and thought about the possibilities of external layouts.
First part can be absolutelly server side, and if coded today you could play it tomorrow with current clients. Server would just load the map, delete default buildables and load custom/random/favourite layout from the text file.
The second one needs deep patching of the client code.
And how would you see blueprints ingame, like ghost-buildings in specific spots?
exactly, but with different color and more transparent to not confuse ppl. You toggle display of the current loaded "blueprint buffer" with a key/bind, peek other peoples current loaded "blueprint buffer" with another key/bind, and copy with another.
That would enable for example a team leader, or main builder to show other players how he wants his base build without typing in the chat every position. Imagine 2 ppl, one loads different blueprints, the second one just aims at him and presses /showblueprint, then looks arround at the ghost buildables and says "its shit, show me another one", after the third one he says "this is pure gold, do it"

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Fast building when clicling on the blueprint ghost is the wet dream of every anal builder, imagine NO MORE 10 second fitting armory in that very special place you like

just load your blueprint, aim at the ghost image of the armory and press LMB, Done! its building

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All around, I think it is a brilliant idea, especially with all those lame builders around.
/me too, now all we need is a trem hacker who knows enough about entities.