The 977 maps aren't -that- demanding either. The huge lag at the start is the preload system working, so that's expected (same thing happens when someone chooses Invoker in DotA). I'm suggesting printing a message informing the players about the preloading. Of course, the map could still stand to be further optimized, but that'll be an undertaking for 0.978 and 0.979, where, finally, the map will be widgetized on release.