I'm okay with the content buy-in. The game works just fine without the add-ons, so you're not missing anything.
My biggest issue is with the lack of any ability to turn down graphics qualities or reduce the number of effects of screen to reduce lag. This is especially bothersome late in the game when the balloons are being popped so quickly they don't reigster and you don't receive money for balloons that you pop. For instance level 70 has an RBE of 10990, but at the end of the round I typically have only collected around $2500.
Fun game, though more than a few bugs. Random events continue to occur while paused or before you start a round. Also, the main cash counter doesn't increase while you're in a round or while you're in research. Don't know if that's intentional but it would make it exceedingly difficult to complete the game successfully.
Fun game, althugh as Jesto said, some badges fo daily accomplishments would be nice "$X in one day" or "travel Xft horizontally in one day". Also, a reset or return to menubutton would be nice.
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 "Vacation Mogul"){kind=icon}
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