As to NOT lose a life by entering an unintentional level, we need to see a preview of the level in some way. I used to be able to do this on my laptop by placing the cursor over the level on the path. A mini version of the level would show up in a bubble. Or you could put up a shadow of the level when we click on it, on the screen where we choose the earned/desired boosters (it could be behind the boosters options in a faded form). That way we can back out if it's not the one we want. I have entered too many levels I didn't actually want to play, and have lost too many lives because we can no longer back out and reset.
But you like players to lose, I think! It makes frustrated players more tempted to make monetary purchases in order to beat/win levels, and finally move on.
This was also entered as an idea called "Hover to Discover"
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