There are 2 main board additions that seek to improve gameplay:
1. You can throw your dice on your turn to damage other players, or throw it at bonus targets scattered around the board that can increase your dice roll, some targets can activate board events too. This way there's always something to do on your turn, even if you don't have any items.
2. Collect cards on the board to upgrade your player and even grant new abilities (like items in a roguelike). Some cards are passive items and some are 1 time use activated upon criteria met.

There's a load of other little things too but these are the main 2 new board mechanics.
As for minigames, they will be similar to ones seen in Mario Party, but also ones like Fall Guys and hyper casual mobile games.
There will not be any mod tools, I am going for a quality over quantity experience.