I just had all of my research planets remodeled (as in module change) and i really find it annoying that i have to go to the trade tab to buy more minerals each time I run out. I recommend that if you are about to install a new module on a planet or your ship and you don't have enough minerals, then make it so that it'll add the price of the mineral needed to the module price. If you don't have enough cargo space for the how much of the mineral is needed though then you'll probably have to go to the trade tab and make space.

plan before hand and make a good estimate on how many minerals you're going to need.

This has been suggested many, many times across the forums. I made the same suggestion myself once.

Auto-buying brings some challenges though. What if the resources you need cost significantly more than you planned for? You might not have enough credits for the daily upkeep (Trust me, this is a bigger problem for high level players than it is for low levels). This would result in ship module damage and a potentially massive repair bill.

A better system would be to have a confirmation box, eg:

This would also be useful when buying ship modules. Overall it would actually result in fewer clicks as well, so less server load.

+1 to auto-purchase with confirmation. I posted the same thing just last week, got the same suggestion. Surely it must be just a matter of time...