It is not as much of question as it is but a suggestion. I just thought that it would be a lot less time consuming that instead of having to close the game and reopening the launcher, that when you close the particular modpack you are playing you could instead press a button that takes you back to the launcher screen or like the others said. Have a checkbox or it just automatically relaunches the launcher or have something that asks you before closing the game if you want it to reopen the launcher.