I have an
HD24XR as well and just got an Allen & Heath System 8 24 channel, 8 buss mixer for 960 bucks to run my system.
For starters.. forget that Behringer. You might as well burn that money. The HD24 is just too good for a cheaply made mixer like that... that will not sound good and break within 3 years.
Honestly, look for a used Soundcraft or Allen & Heath 24 channel/8 buss system that has either inline monitoring or enough tape inputs to allow you to monitor all 24 channels.
Allen & Heath GL2200 is a great choice... about 1600 bucks.
Soundcraft Ghost 24 is good choice as well. About 2400 bucks.
These were the used mixers I was looking at for my own system until I came across the System 8 248 mixer.
Note--I'm highly prejudiced towards British consoles!
Forget the Mackie because in six months you'll be shopping for expensive preamps and eq's to get past that thin, bright, grainy Mackie sound. (I know, I just got rid of a Mackie CR1604.) Why buy preamps for extra money when you can have good sounding preamps on the console? Same with EQ. On my A&H I get a fat 4 band parametric.
Not bashing on the guy above with his 32 channel Mackie, but notice how he can pair it up with his favorite preamps? All that money and you still need better preamps? No thanks, I'll stick w/ my A&H's preamps!
Within your price range you should be able to get an amazing Allen & Heath or Soundcraft that you will prize for the remainder of your recording days. They are really good for those of use that can't get an SSL, Neve, Neotek or likewise. At least that's my opinion.