A lot of players have 13 star heroes as it is now. If there were safe spots or if stars don't get lost, those players would all be at 15 now.
Especially that the CWF is giving out a ton of purple medals, imagine how many 15 star heroes and players there would be.

Star system has been fine as it is since the beginning. Amidst all the turmoil, frustrations, and complaints, it has weathered all those storms.
15 stars is not for everyone, not even close. So just accept it as it is and focus on other parts of your account.