Optional Non-Krogan outpost on Eladden

I don't get why we can't establish second outposts in general.   There are a lot of fantastic areas,  even areas that should make better locations than the ones the game gives us.

Also,  why can't we set up our outposts ourselves?    They're very blocky and modular,  they seem perfect for a Fallout 4 style settlement build,   but even more simplified and streamlined with the various modules you already see.      All you would need is a bit of work and some sort of beacon to place that designates an area as an outpost or not which keeps enemies from spawning and designate existing structures as outposts.    

I want to make an outpost in that valley area in the far north on Kadara,  where you fight the Kadaran Architect.    The moment I saw it I thought it was perfect.