I use EI because I have no way to tell exactly what my plants need. If I want heavy growth, I dose three times per week and do 50% water change each week or two if I'm lazy. If I want slower growth I does once per week and do water changes every 2-3 weeks. It just depends on what I'm looking for.
I have my water change procedure down so it doesn't take much time. I'm lucky enough to be able to just fill the tank with a garden hose and the water parameters, temp, etc are fine year round, and my tank is only 46 gallons.
I dry dose. I have a week pill container, you know the one that has a container for each day of the week. When I do a water change, I use my teaspoon measures and fill each day for the week. Then each day when I feed the fish, I just dump in that one days ferts, macros or micros. Takes < 1 second to dose.