If you want to play the game with fewer surprise effects and proceed more strategically, you can change the rules as follows:
A player may only place a Kahuna bridge on a free connecting line between two islands if none of these two islands is under the opponent's control (none of them is marked with one of his or her Kahuna tokens).
If a player can remove a Kahuna bridge by playing two suitable island cards, he or she may place one of his or her own Kahuna bridges on the connecting line that has thereby become available, without playing an additional card. Here, too, he or she may only place the bridge if none of the two islands is under the opponent's control.
If you want a game that relies more on tactics and less on luck, you can use the following variant:
If a player draws a card face up, he or she must place it face up in front of himself. He or she may play it like the cards in his or her hand, and it also counts as a card in his or her hand.
When an experienced player plays with a beginner or when it becomes apparent that the players have different playing abilities, they can also play with a handicap.
In this case, after dealing the cards the less experienced player may place one, two, or three bridges of his or her color on any connecting line of his or her choice, depending on the agreement.