This game took longer to develop than the original. Yes the costs of activities are the same, because they are the costs that make for a balanced game. The basic design of the game is the same, just as the basic design of Medieval : Total War is the same as Shogun: Total War.
You don’t change things for the sake of it, but to improve upon it. Here are some of the changes in Kudos 2:
Different events at work -> Each career has it’s own work events that are specific to your career
Performance affects work days now, so being good at the job actually directly affects how your day goes.
Customizable avatars -> The player can choose their own avatar from tons of different combinations
Work clothes -> People with office jobs change into a suit for work, and everyone wears sunglasses if they buy them
New UI -> The entire user interface is reprogrammed and designed from scratch
Restaurants -> The player now chooses individual menu items, all of which affect the character in different ways
Birthday Parties -> Each year culminates in a birthday party which raises or lowers your spirits based on your popularity
Better NPC AI -> The friends have far more sophisticated AI than before, making more intelligent decisions regarding socializing
Gossip -> Friends will now gossip about events such as bands and plays and museum exhibits, tipping off the player as to when to socialize where
Personalities -> There are more personality types for friends in this game, such as extrovert, honest, optimistic, persuasive
More Character AI -> Extra characteristics have been added to the players character such as optimism and extrovert
New MiniGame -> The minigame for playing video games is entirely new, and the gambling game is entirely new.
Dynamic Background -> As time passes the background dynamically changes to show sunsets and stars at night.
Alcohol effect -> The background goes wobbly as you get drunk
Dynamic UI -> When it’s winter the UI changes to blues and whites rather than summers warm oranges.
Widescreen support -> Final build adjusts dynamically to 1280x768 for widescreen PC’s, especially laptops.
Faster game -> The game moves quicker now, with less days in a month to make the full 10 year game quicker and more activity-packed.
Positive attitude -> A lot of the games variables and content has been reworded an designed to be more upbeat and positive.
There are also some new social activities, solo activities, books and things to buy, plus more text variety and probably more I can’t remember.
I appreciate that you might have wanted the game to be radically different, but I’ve concentrated on improving on what people enjoyed, rather than radically re-inventing the game.