Sounds like you know what you're doing. Mother Nature and the KISS principal at work.Ive done a dirtied tank in a 5 gallon. Worked fine. I kept the lighting between one and two watts per gallon. Used top soil for dirt. Just normal inert gravel to top off and kept soil layer to rather less than an inch deep. I planted each plant by holding the plant roots to my muddy soil and tipped a little gravel over to hold in place, then once all plants where I want them just gently top off with more gravel. No forceps involved. My water quite hard so I didn’t have to agonise over any additives and just did it really simply. No rocks or ornaments either, just plants. I did use water lettuce initially to soak up the rush of nutrients in the water for the initial period of 10 - 12 weeks and removed them once root growth of the floaters began to struggle as this signalled the tank was now settled. I have a little guppy grass now as a nutrient hoover. Never really had a problem with algae. Hope you get on OK with this. I like a 5gallon tank, very easy to deal with!