You said that you can add EQ and effects in the recorder, but that mixing.
You have a recorder/mixer combo, and if you EQ and add effects during your recording, you are mixing while you record.
Hell, I even mix while I'm songwriting.
I write in guitar pro, which has individual volumes and even panpots for every channel, so when I finish songwriting, I know how everything has to sound, I just apply that to mixer (Sonar in my case)
Mixing is always there, even if you don't realize it.
As for mixing gear, much more important than the mixer itself, it's your monitoring system.
I guess the most important requirement of your mixer is to have the sufficient number of channels you are planning to mix, which is why Software mixing is more and more popular.
If you want to mix 24 tracks, you need a Mackie 24x8 or similar, and a HD24. About 6000$.
Or, you can get any DAW software in your computer and mix 24, or 32, or 64, or 124634 channels, and each with tons of Plug-ins for EQ, compression, limiting, Reverb.... The only limit is your computer.
Bottom line: Mixing is pretty damm important, not to say mandatory, so if you are making a hardware only studio, start saving some serious bucks
