When you are adding new plants you sure can drain the tank pretty much all the way. If it is drained too long, though, the leaves that grew under water do not like it. Keep misting.
When you refill the tank put a plastic bag or a plate over the substrate and fill slowly, allowing the water to seep in over the edges. This will minimize the cloudy water and not disturb the substrate.
The ammonia production from the ADA products can get pretty high, and the nitrifying bacteria do not like that, and many plants do not like that high ammonia. I would follow Amano's suggestion about plenty of water changes. If you do not want to follow that schedule exactly then here is an alternate idea:
First few days: Do enough water changes (frequency and volume) to keep the ammonia at no higher than 5 ppm.
After the first few days: Do enough water changes to keep the ammonia closer to 3 ppm, and the nitrite no higher than 5 ppm.
If you start with no source of nitrifying bacteria then the fishless cycle takes about 3 weeks. The soil keeps producing ammonia for at least this long (I have heard about a month) so you may not have to add more ammonia.
If you are running the tank without fish or shrimp and the soil is no longer producing ammonia, then add ammonia to 3 ppm once a day until you are ready to add livestock.
Prime is one of the cheapest dechlor there is!
If you are working with a really large tank so that the cost of Prime is an issue why not just fill it about 25% or so, then you will probably have to do water changes every day, but a lot less water than if the tank was full.
I use Chloramine Buster, dosed at about the same rate as Prime, and use an eye dropper to measure it out, even for my largest tanks. It is cheap!