Actually I never upgrade outposts.  I plop them down for resources or terrritory and then forget about them.

Fully agree on this. Consulates are the most rediculous, but some of the others are powerful too. The whole 3 turn limit was back in a time when there was very little to build and was meant to prevent cities from being instantly finished doing everything they could.

There are now enough buildings that I often cannot complete them all before the end of the game and this 3 turn limit is no longer necessary. Not to mention it functions poorly with the idle bonus that is rarely utilized.

The Outpost idea seems to clearly be a copy of their Mechanic from GalCiv2. Even Frogboy did a supposed slip reference as a joke in the original post about the outpost upgrade system.

I say if you are going to take an idea that worked previously then take the whole idea not just part of it. That being said I don't think there is anything wrong with it but I think they should actually fully copy it's mechanics. Use Pioneers to upgrade the outpost and resources instead of making the cities do it.

Newly built cities are often closest to new resources. As such their production queue gets filled up building resource buildings and outpost upgrades. When instead the city should have more important things to do, like building up it's own infrastructure. Not to mention the whole system is very confusing since it does not tell you which city's production queue is going to get used up whenever you upgrade something.

If outpost and resource buildings worked like starbases in GC2 then you could just use your inner cities with higher production to pump out pioneers and build up those front line resources, the same way you build up front line starbases in GC2. 

Also have an upgrade so the outpost can actually defend themselves. It's kind of annoying that they are defenseless against even an enemy pioneer.

I wish I could upgrade outposts.

But with the 3 turn production minimum, the new never ending production queue from having to queue every single thing on a map, including having to upgrade wild improvements through cities that aren't designed for production, there's simply no time. I don't even get halfway through my critical improvements by the end of game.  The game would be several times over before I began to think about upgrading an outpost.