Boosts should not be refunded, people should be cautious on where they use their boosts, and if they want to have all of their eggs in one basket they can do it at their own risk.
That being said, the high refund penalty does lock players in a situation where their teams can be rendered obsolete with every update, discouraging them from playing. It is starting to happen to me.
I say allow for people to be able to refund 10 boosts per week, for free, before they start being penalized.
That would give players some flexibility on changing their team little by little, while not giving them a full blown refund of the boosts.
Moreover, players will have to chose between resetting their teams boosts little by little, or investing those boosts on tournament dinos, without getting the option to completely boost a tournament team, as only the 10 will be refundable for free, given they have not used the refunds already that week.