The Holy Grail?

I'd like to convert my 70-gallon tank to a low-maintenance, but still
high-tech, plant tank.  I want to do water changes and prune plants no
more than once a month.  I also want to keep my existing stock level
of fish - 0.5-0.75 inches per gallon of mostly 2-inch fish.  I still
want an interesting tank, with at least a few challenging plant species.

I'll retain my 4x40W fluorescents and CO2 injection, and build a DIY
30W substrate heater. Filtration will be with a single Magnum 220.

The choice of plants is proving difficult.  I've decided that most
stem plants are out - they grow too fast and need to be uprooted too
often.  I may use a few for accents, but the bulk of the plants have
to be relatively slow-growing.

But, if I don't have any fast-growing plants, I am afraid that my fish
load will be too high.  I have a compromise in mind - I'll have lots
of fast-growing floating plants.  I can live with having to throw away
a few handfuls of Frogbit (Limnobium) or Watersprite (Ceratopteris)
every week.

These floating plants are going to shade my tank.  This means I will
have to stick with rooted plants that will grow in relatively low
light.  So, what choices do I have in this area?  Java Fern
(Microsorium), Java Moss (Vesicularia), Crypts, Anubias, Bolbitis and
maybe some Swords come to mind, but what else?  I'd like to have
something out of the ordinary.  Can anyone recommend something

Does anyone have low-maintenance setups that can sustain a relatively
high fish load and still grow some "difficult" plants?