I'm going to explode if I read this one more time. The only thing that is changed is the setting. The game still has all the problems that AC always had and then some more.
The pacing in this game is atrocious, the story is an unfocused mess with characters appearing and disappearing and time jumps that make no sense. And that is without mentioning that pretty much every mission up until sequence 7 is some sort of tutorial for things you have already done because they give you access to the whole world starting in sequence 3.
The side content is pointless like in III where collecting shit also gave you nothing.
I like the game a lot but let's not pretend that from a gameplay perspective this is any better than III.
I don't know man. Game is VERY streamlined. With AC3 many ideas that they had, they made them way to complex/boring/tedius while in AC4 they took the same task and just made it simpler.
For example.
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Crafting
AC3 - First you need to find and save and level up the artisans.
Then you need to hunt/forage for sometimes 3 different materials.
Then you need to (IIRC) try to combine them and you might get lucky and get a recipe?
There are also something like 100 different materials you need for crafting..
Tedius/BORING/Overly Complicated
AC4 - No need for recipes except the elites.
List of materials is less than 20 not 100s.
2 materials max per item. Many items just need 1.
And for ships there are only 5 mats. Soo Streamlined.. because it was way too tedious, way too boring, and way too complex in AC3
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Economy.
AC3 - Umm wtf? did anyone actually gain any enjoyment from this garbage economy caravan system? It was Tedius, boring and also overly complicated.
AC4 - No body enjoyed that crap... lets gut it, Everything is sell-able, everything is buy-able, economy is static, Because no one plays AC for their advanced trading system. Get rum and sugar........sell rum and sugar.
Streamlined.
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Stealth
AC3 - Wanted status in Cities? Posters, Town criers?
AC4 - Gone
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Traveling
AC3 - Run Loading, Run loading, Sail loading, Swim loading
AC4 - Playing, Fighting, sailing, running, swimming, climbing, Loading.
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Traveling part 2
AC3 - I'm walking at a snails pace in all this Snow... And I need to walk for another 10 minutes to reach the next point. Or I could Fast travel and wait for 10 minutes for the game to load... Decisions Decisions
AC4 - I was Just in Jamaica And Now I'm in Nassau. With no loading screens. And during my Journey to Nassau I did a whole tonne of stuff on the way.
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Animus
AC3 - Oh gawd I hate playing as desmond, what a terrible character.. Can't I just spend more time as Connor PLEASE?
AC4 - Thank you Jesus.
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Thats just off the top of my head.
If you want to talk about setting, story line, animation, Character, acting sure then you might have a discussion about AC3 vs AC4.
But when it comes down to fun being had. AC4 has it in spades while AC3 i felt bogged down in minutia constantly