I also live in Indy, and for the record, the city is *NOT* going down hill and in fact is growing in population, and Hamilton and Hendricks County are both in the top 25 fastest growing counties in the entire US!! (unlike Hamilton County, OHIO which is *decreasing* in population!...though Warren Co. is growing)
And also to set the record straight, while I would not have closed Verizon Wireless Amphitheater, they're completely re-doing White Water Park Amphitheatre AND Lucas Oil Stadium is supposed to have state of the art acoustics for a stadium since speaker company Klipsch (which is based in Indy) is working on the sound system.
But the bottom line for no amusement park is location...SFGA, SFStl, SFKK, HW, KI, and even CP!!...it would make no sense...similarly to Indy not having a baseball team with the Reds, Cubs, etc. But maybe one day it's possible as Indy continues to grow...since Indy is the most populated city in the US not located on a major body of water, so that's pretty good!!