Explanation:
The prices of airplane tickets keep decreasing. To make the most of this development it is good to promote the inland flights. Tourists only spend short time in Cuba, so it is useful for them to travel by airplane. If they rent a car they will spend more time travelling than actually visiting the destination. Although this is only an improvement for tourists, extending train and bus networks also helps the local people. With the revenues of tourism Cuba needs to improve these networks. Tourists do not have the opportunity to go far besides their accommodation area, so their obligated to stay in the resorts. This causes centralisation.
The explained recommendations are a huge investment for the economy, but on long term the revenues will make it profitable. The consequences for the environment will not be dramatic. Of course, there is cause, but that is not in agreement with the benefits. When public transport improves, Cuba will get the opportunity to show it's diversity, but about that more in recommendation 2.