The nine-ball event was race to seven up to 2014, the year it was changed to make WPA sanctioning possible, but that sanctioning lasted just one year (2015 only) and, I feel, the races should have reverted to seven then and there.
The purists will always take exception, but race to seven wasn't exactly producing unworthy champions, as in the last ten years of race to seven, the champions were: 2004 Souquet, 2005 Reyes, 2006 Souquet, 2007 Fiejen, 2008 Souquet, 2009 SVB, 2010 Reyes, 2011 Orcullo, 2012 SVB, and 2013 Pagulayan. All of them but Feijen are now Hall of Famers and Feijen is sure to get in soon.
Even at race to seven, the Derby City nine ball was always the domain of the elite. It's because the format asks the top players to do their own heavy lifting. With race to seven, the late rounds of the Derby have always featured the game's giants and the winner always had beaten champion after champion, and, with few exceptions, only the all-time greats were up to it.
I think it's time to go back to race to seven. A middle ground might be race to seven until Round 10 and then race to nine.
The alternative, of course, is to reduce the field size. When I saw that the field size was well over 500 players, I immediately changed my flight home, knowing in full that the event would go well into Monday morning.
It is obvious to any onlooker that late entries were permitted, and that was a mistake. Outsiders looking in should only get in through the wait list.
I'd do entries the way Matchroom does. Fix the field size, give the elite invitations and make everybody else sign up online by an announced date. Who would get the invitations? This would need some discussion, but I'd go with a) everyone who is ranked in the top 32 in either the WPA or Matchroom rankings, b) anyone who has ever won a Derby City event, and c) anyone who got to Round 10 in any event in the previous Derby City Classic.