Hi Clapfoot,
Load times are generally proportional to how much memory is being loaded. You can use the console command obj list to see all of the assets that are currently loaded and how much memory they are taking. Use this list to identify and prune out assets that you don’t need in a particular level. For more details on this process, see the following blog post:
https://www.unrealengine.com/blog/debugging-and-optimizing-memory
Once you’ve pruned unused assets, look for ways to make use of asynchronous loading. Using asynchronous loading, assets that aren’t needed immediately don’t need to be loaded when the level starts, and can be loaded in the background later. See the following doc for more details on setting this up.
https://docs.unrealengine.com/latest/INT/Programming/Assets/AsyncLoading/
Best,