The jungle look isn't necessarily overgrown and messy, In my case the 15g is my guppy and snail breeder. the bottom of the tank has very little bare substrate, and with a small piece of driftwood, the tank looks like a jungle. plants are organised but not necessarily placed as well as some might place them. As far as the snails and guppy fry are concerned, it's fabulous, and my fry survival rate thus far is really good. as the crypts get bigger, and the java moss spreads it will be quite like a rain forest below the leaves. I ike it, but I won't be entering any aquascaping contests anytime soon.
When in doubt I start trimming, just not a lot at once because I would prefer not to see certain types of algea going nuts in there.