The two lanes headed uphill both have to shift lanes to the right in the middle of this very large intersection, without adequate guide lines, signage, etc.

Possible solutions?

-A left turn only lane
-Lines clearly painted within the intersection
-?

The photo is taken from the left lane (designated straight and left turn). As you can see, it faces oncoming traffic. If you want to go straight through the intersection, you need to fear oncoming traffic that assumes you are turning left. You also need to be worried about cars in the right lane, who do not know that it is not safe to go straight through the intersection, as opposed to staying to the right lane at the far side. (Them doing this means you get cut off and are driven toward oncoming traffic.)