Most speculative potential applications
(Warning: this page contains highly speculative information.)
previous: further improvement at technology level III
Some things can fundamentally only be done in meso- to macroscopic size scales. Not at micro- or nanoscales.
Those things will also be improvable by APM but since complex products composed out of a multitude of advanced AP metamaterials are already speculative,
technologies based on their interplay are even more vague.
Applications which make heavy use of electronic optic magnetic and other non mechanical physical properties will
require a lot of scientific investigation to make less vague predictions (see: Non mechanical technology path).
Some random mix of ideas
- diamondoid artificial ion channels (very likely possible)
- self cooling cryogenic cells for e.g. synthesization of small non-diamondoid molecules
- mining - advanced bulk preprocessing
- generation of radio waves by mechanical rotation of charges
- optomechanic applications
- neutral molecule carriage particle accelerators
- non biological multi limbed sensory equipped shells of all forms including humanoids
- artificial brains that can accommodate human consciousness scanned from brains of deceased persons
- use of APM for nuclear fusion
- successful terraforming - see air using micro ships
- solid state earth core probes -- this one probably takes the cake from all the ludicrous ideas here
- Nanomedicine - A relevant book - 
Even further ahead there might (or might not) lie a zero sum situation - again. Warning! you are moving into more speculative areas..
Ultra large scale stuff
- novel space launch facilities - there are some crazy ideas there
Regarding the gas (and ice) giants:
- littering of gas giant atmospheres with permaflying fusion power planes that collectively beam unfathomable amounts of laser-power to receivers in high orbit
- usage of gas giant atmospheres for something something ???
- complete conversion of matter of larger scale asteroids to something something ???
- Some large scale mass relocation projects for something something ???