If this isn't a loop then please tell us what is !!

However with that said, even with a loop all the oil in the loop below that horizontal line will drain back into the pan - very easily and quickly when its hot. What little is left above the pump is all you have to prime with. Then that long loop as to fill up before you have continuous flow and pressure.

So while a loop is a good thing, you still want the feed line as short as possible. As for that check valve, its pretty fat - I doubt its very restrictive to normal flow.