You got the concept down. high and low spots make it more difficult to dry start IME, plants in the low spots get too wet and plants in the high spots dry out. If I had to do it again Id make my substrate flatter. Amd most people suggest not letting the water level go above the substrate anywhere in the tank, however it hasent been a problem in mine for the last 4 months lol. If I were to do it again Id put some Miracle grow under the substrate, but some root tabs/osmocote tabs worked ok. Youll have to look up each plant you want to dry start seperately. A good amount of the plants out there will do fine!