Yeah we're actively working on the distant object issue, it's more about culling/crossfading and we've a lot of blocks to go over. Still, if you do find some that are glaring like that, it can't hurt to make a bug report about it. The bush is known, I'll add it to the KI list if it isn't already. The settings that affect that, to answer you, are LOD distance, View Distance, and Object Quality.