The DerivedDataCache has caused massive issues by using up my entire C: drive (which is a small SSD) despite the fact i have installed UE4 and everything UE4 related to its own 2TB Hybrid HDD. This has caused huge problems from crashing the editor to taking upto 5 hours to complete a copy and paste of a large group of BSP’s that since fixing the problem now only takes about an hour. I also had to manually change the engine.ini file which was a tedious task.
This would be a great improvement if it was given as a choice or if the user doesnt select the default install dir then it should go with the rest of the data. Possibly a its own DIR within the UE4 root directory of the selected install location.