Let's see. A downtown stadium tying up 4 to 6, or more, blocks sitting empty for 280 days a year, bringing no life at all to downtown. In its place have those same blocks occupied by offices, retail, restaurants, residences, etc. bringing life to downtown just about every day of the year.
I will take the second choice.
Some simple math... Royals average at least 15k per game in attendence. Multiply that by 80 games.
That's 1,200,000 people who would be milling around downtown before, during and after a game.
Besides, currently there are plenty more than just 4-6 blocks sitting empty right now. And I can tell you that they're not bringing in 1M+ to downtown.