For low tech or high tech, I recommend aqua soil. Obviously inert substrates work as well, but I have seen anecdotal evidence of my low tech nano tank with ada amazonia powder growing montecarlo and marsilea really well and in my opinion, much better than my inert substrate tanks.
But honestly, it all depends on a person's budget, goals, etc, and it's a pretty cheap experiment/try to just go with BDBS or PFS. So why not? But if you can, definitely try a tank with aquasoil, and especially powder form, for carpetting. I would do reg AS with a top layer of powder form. or if it's a small enough tank, just powder.