In fact, in A7 you need never put a wait() after level_load.

In A6 you needed that wait() before you could create entities. There was a simple reason, level_load() in A6 was executed not immediately but at the end of the frame cycle. This was changed with A7. It's neither because of "resources consuming" nor will it "crash".

I also have often seen newcomers getting advices like "try a wait() here" or "try a wait() there". This never helps. It just wastes time and causes frustration.