Your drives are all doable but you are right to add plenty of time to Google estimates that are just not 'real world'. A computer thinks us mere humans can drive at the speed limit all day without facing traffic congestion and construction delays never mind having to fill with fuel, use the bathroom, eat and actually rest. Fort example Fish camp to Lone Pine will take closer to 6.5 hours with the brief stops mentioned above, plus any extra time if you plan to sight see. LA is LA and once you hit the area there is no telling how much time it may take to get across the city especially in peak periods, but you are in good shape.