There have been earlier discussions about economy upgrade being cumbersome for players, especially building mass storages. You need to setup templates to make it less micro-intensive and also make sure you walk around with enough engineers to build them. One suggestion was to remove / lower mass storage adjacency to reduce the need for building them.
I've made a mod which is a compromise, trying to solve the above problem:
* Mexes are able to build mass storages themselves, just like an upgrade. This reduces micro to a single click and removes the need for a template.
* You are still able to assist the mex to make it build faster, just like any other builder.
* The normal way of building mass storages are ofc still possible
Please try out the mod and come with your opinions, is this something that would benefit the game? The UI logic isn't polished so there may be weirdness / bugs
Mod is called "Mex builds Mass Storages", search for "Mex builds"