It seems that the more successful your meditation is, the more lavish the surroundings of your next life (e.g. rebirth in a heavenly realm following the attainment of certain meditative states). However, this seems contrary to the goal of non-attachment, and a more logical karmic result of meditative attainment would be rebirth in some setting that would most easily propel you into a monastery. So, why does progress in meditation cause rebirth in a more worldly setting?
As I have understood, Heavenly and Hellish realms are determined by state of mind. It is well said that two people can be walki g down the same street and one is in hell and other is in heaven. Heaven and hell is the way we experience this universe. So if you do meditation and you get born in a monastry world setting and it is still heavenly as it will all be experienced.
Rebirth in a heaven doesn't mean more worldly settings.
Heaven can meditate and enlightenment easier than human life. But partial correct that it will also lead to get lost eaiser when there were full of happiness and no suffer there.
Your old karma will lead you to more worldly setting, Not meditate.
There are 2 types of meditation.samatha and vipassana. Samatha which concentrate our mind lead us to obtain samadhi and dhyana..samatha meditation is was there even before the enlightenment of budhda. Ex: 5 monks who were meditating with sidhdhartha had the highest level of dhyana even before sidhdhartha's enlightenment. Samatha helps for rebirth in heaven and brahma according to the level of dhyana. But meditation introduced in buddhism is vipassana. Which gives you wisdom and nibbana. Even when someone do samatha and got dhyana is definitely end up in world of brahma. So as brahma get very large life span he might lose period of dhamma when he leaves world of brahma. So guiding in buddhism is to practice vidarshana and end up with nibbana and not to practice samatha and end up with world with more attachments.