If I may give one positioning suggestion for your Deep B before getting into the meat of your other question. Try trying one step up from your current starting position and you might develop a better angle.
Now as for your eyes question... The quicker that we can get our eyes to where the action is, the easier it becomes to focus on what we need to focus on. Don't let the ball turn you... as soon as you're comfortable knowing you're not going to be hit by the throw, get your eyes to the base and find the defender. The defender is going to let you know where the throw is going by their actions. And yes, the focus should be on the defender's glove. The defender will take the glove to the runner, so if we focus on the glove we will see the tag when it occurs.