Festering Skies and Resources?

Here after some more playtime - without Raiding and Stealing Aircrafts from Factions - do you find the balance of Resources good in Festering Skies?

I try to run on Legendary, as I have a good hold of the ground-missions (the basic gameplay) and don’t really want to change the challenge in this aspect by lowering difficulty, so no free Manticors with bases. And unfortunately I do struggle to fight of the Flyers.

I play without Raiding, Stealing, and almost without Trading.
Resources are ok.