I played Alpha Centauri after Civilization 5 for a couple of months. It does have a lot of issues that many nostalgic people probably fail to remember, i will just list them here:
1. Square grid -> it diminishes any sort of terrain combat tactics since terrain is less of a hinderance for your troops to move effectively. Moving diagonally you can pass any sort of rocky terrain that would've otherwise slowed you down. On a hex grid if you try to bypass a a hill tile, you need to move through two tiles. On a square grid it costs you nothing to bypass rough terrain.
2. Stacks of doom -> it has already been talked a lot about this so i will not go into detail here. Combine that with pt. (1) and you got a very simplistic combat system where you can just go Yang spam rovers and roll over all the opposition
3. ICS -> AC is one of the worst known Infinite City Sprawl offenders in the history of 4x games. Efficiency and Drones were never good enough limiting factors. Simply put, more cities = better. Drone management is not a difficult task at all, and once you energy production is high enough it becomes auto-sustainable by diverting some part of the energy your citizens are collecting to psych (and you don't need to divert to much simply because the game offers tons of buildings that add multipliers to science and psych. You can have huge big cities and MANY of them.
4. Simplistic growth mechanic. Just get +6 Growth, which is not hard to achieve at all with social engineering (democracy, planned economy), Children Creche building. And you get +1 pop per turn! If you have food to spare, growth is never a problem. You can have HUGE cities in a moment notice. And if for some reason your faction lacks one of those social engineering policies or has a -Growth modifier you can overcome it with a golden age, which again is not that difficult to have by diverting for a few turns energy to psych.
5. Complete and utter mess tech tree. I hope no designer will ever try to implement something as horrible as AC's tech tree. And it's horribly balanced. Industrial Automation anybody? Get this one and you already on the path of having the strongest economy. Get Doctrine Air-Power and you already a serious threat to everyone, because to combat Air-Power your opponents need to reaseach tons of stuff just to get the AAA armor upgrade which is on a tech path rarely one will dare to get before Doctrine-Air Power.
6. Chop'n'Drop, why go for grav ships, hover tanks when you can clean entire cities and their garrisons with this cheap tactic. The entire package is comfortably sitting in one tech: Man Machine Interface. You get 'Copters that can attack for every movement point (most powerful unit ever in any 4x game) and Drop pods to immediately capture those cities with your rover.
7. Simplistic economy. Energy in AC basically translates into everything -> production, happiness, science. This system is very easy to exploit into your favour.
8. Water cities. Worst feature of AC. They do not really add more gameplay variety. in SMAX you can basically further ICS your path to victory ad ifinitum. because you can now get some decent amount of production in them as well. And the amount of food and energy you can make with them is incredible. Rinse and repeat. Not strategy required
9. People like to talk about unit builder how complex it was but in reality it had a lot of superflous stuff. How many of you have built Colony modules on rover chasis? How many of you have built needlejets with armor? Of course nobody. How many of you have built 4-1-2 rovers for attacking and 1-3-1 Garrisons for defense? You will always want your best weapon for attacking and best armor for defense. So the real meaningful choice are those extra features that you add to your units: Drop Pods, Nerve gas, Amphibous, Anti-Air, SAM, ECM which in other Civ games are already represented by different units. Your soldiers with ECM are your standard "Pikemen" against Rover "Cavalry". Rovers with ECM are you standard Civ "Lancers" and so on. You will not win the game because you designed some unusual unit with some special features, it's your standard 4x strategy that will win you the game.
10. The real terraforming (raising, lowering terrain) was a mid-game -> lategame tech, wasn't such a big deal after all. By the time you would raise a big mountain (>3500m) for your solar colectors to be useful you would've probably won the game already if you had so much money to invest into all that terraforming. Raising a "bridge" towards your opponent's continent was fun, but by the time you can do this, you might just as well have Chop'n'Drop availalble.
11. Factions, i always felt like it broke my immersion the fact that some idiot allowed for such mentally sick personalities to board the humanity's ship to alpha centauri, the last hope of our survival. Chairman Yang? Really? Are you nuts? What is this psycho doing here? Ship construction was financed by Morgan, so i don't see why such mentally unstable freaks like Yang and Miriam had to be allowed on this ship in the first place. As for SMAX faction leaders i prefer to think those never existed.
Oh and who was talking about AC diplomacy? Have you seen Morgan declaring VENDETTA on Gaia because of some rumors about her walking naked in her private garden?
12. The stupid ecology pollution thing. I am talking about the production cap before you start messing witht he environment. Good idea, but the mechanics behind it was horrible. The concept of clean minerals where you had to build those Alpha Centauri preserves, then raze them and build them again thus raising your clean minerals cap by 1 every time. I hate that thing.
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