Adamant mod will give you no playability in SP right now, because the AIs are not modded yet.
If you can find humans to play it with, then go for it. Just keep in mind that I have not gotten to Weapons yet, so everyone uses the same weapons.
FQM can be used with nearly any other mod, so it can easily extend the playing time of any other mod. Just play some games with FQM Deluxe: it makes the maps much richer and more varied, and overall gives (IMHO) a better experience than using the standard quadrant/system schema.
Proportions games take many many turns, so that mod has a lot of numbers of hours.
P&N as a Pirate or Nomad takes a while too, so that can easily be many many hours too.
