Those look good I think that idea could be big in a lot areas. Concerning the drip, are you sure that the drip is going to do the job for the entire bed? We have a lot of experience with drip and the type of soil that a lot of people
plant in has toooo much compost to transfer water. So we are going to put liner under the bed to trap all the water. We also noticed that some of the soil that we get transfer water much better than others....our experience is in flower beds. .....Anyway this is really a good idea.