These are valid points . From someone who has a solar grid tied setup . These problems arent really that big of problems to prevent one from going with solar grid tie . I do personally see a need for the homeowner or power company to have a battery backup or some type storage system if this is to work long term though and main stream adoption. My reasoning is this imagine you have 100 families. All with solar 75% are working and 25 percent unemployed or retired . During the day your power company would benefit greatly if they could absorb this extra juice and disperse it during the night if they may be experiencing brownouts due to power grid overload .