head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Optimization · Pure Optimization
A deep 3.5E optimization puzzle where prestige class chaining and feat synergies determine party effectiveness.

Optimization · Pure Optimization
Mastering interlocking social engineering and tech-tree systems on a programmable alien world.
Neverwinter Nights 2 leans Optimization (Pure Optimization); Sid Meier's Alpha Centauri leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Neverwinter Nights 2
Tactical pause negates twitch; positioning is deliberate not reactive
Sid Meier's Alpha Centauri
Turn-based; no twitch element at all
Sid Meier's Alpha Centauri leans a little harder on reads, though the gap is small.
Neverwinter Nights 2
Companion AI and enemy scripting are fixed, non-adaptive routines
Sid Meier's Alpha Centauri
AI faction leaders follow fixed personality scripts
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Neverwinter Nights 2
Hidden enemy stat blocks and variable dungeon RNG create unknowns
Sid Meier's Alpha Centauri
Xenofungus and psi combat add some irreducible randomness
Sid Meier's Alpha Centauri leans a little harder on optimization, though the gap is small.
Neverwinter Nights 2
3.5E feat synergies and prestige class planning define optimal builds
Sid Meier's Alpha Centauri
Tech tree, social engineering, and base placement are essentially solvable
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.