Wow so many options!! We carry a 12 cup Mr coffee for our normal use.
Instant seems to be the most obvious choice for backpacking or boondocking, but We prefer fresh perked coffee.
Over the years, when boondocking:
(1) we tried using a 4 cup percolator, which worked well, but had to be watched or timed..
(2) We tried using a small sauce pan one time and a percolator the next to boil water and poured the water thru coffee in a filter.
(3)Then tried boiling water and coffee in the sauce pan, which also got poured thru a filter. All of which involved a bit of inconvenience.
(4) We tried a 650 watt Mr coffee 4 cup coffee maker powered thru an inverter. It took about 5-7 minutes to make 4 cups and only used about 4.5-5.5 amp hours from our batteries.. It only weighs aprox 1.5 lbs and makes great coffee, but the inverter weighs about 3 lbs!!!
Never tried a solar coffee maker..
In the end We decided to swap out our 9 cup stove top percolator with our full size Mr coffee, depending on whether we have a full hook-up or boondock site.
I guess you just need to define your priorities and options and go from there...
Safe travels and all the best..