Re: Industry standard
I'm not sure we will have as stong a standard as Yamaha has been in the future. Yamaha was miles ahead in the low and mid ranges, and really only in the last 12-24 months have there been reasonable competitors for similar or less money.
Your budget seems to be $5k-$10k. In that range are the Soundcraft SICompact and SIPerformer, the A&H GLD, the Pro1, and I think the Digico SD11 at a bit more. If you add the stage boxes to the Behringer, that's probably in this range. Without them it's cheaper. I think there's a Roland option, but the M480 is more money. There are less conventional options like an IPad-controlled ILive, SAC, and a few others as well.
IMO, there are basically 3 workflow choices - the 1:1 model of the Yamahas, SICs, Rolands, and Behringer (though the Behringer also has scribble strips), the fewer faders with scribble strips model of the GLD, Pro1 and most of the larger mixers above this price range, and then full software control like a surface-less ILive or SAC.
Since you are buying just one mixer, I would try to focus on teaching transferable concepts like not assuming the jack on the back labeled "1" is always the far left fader, and trying to get people to learn how to mix rather than how to use a specific tool.
To answer your question directly, the LS9 is surely waning. If you can get a great deal on one, it might still be worthwhile, but until/unless Yamaha updates the lower mid market, folks will continue to stream away to the other better choices for the same or less money.
