That's my whole point...the ONLY thing that should take any priority over anything else is the vocals, especially lead vocal. You always have to make sure the lead singer's mic is heard before anything. Everything else is equally important to a good mix, and bass is one of the very easiest instruments to mix and make sound good, so I'm not getting where this tremendous level of difficulty is coming in.
One more clarification and then I am out. I swear.
Bass is, in my opinion, the easiest instrument to get sounding good. Which is why in times of challenging situations I try to get bass worked out quickly.
It is unrealistic to think each instrument should get equal time.
Drums take longer: more mics, different sizes on each kit, drummers with Neil Peart kits with 8 toms, different drummer dynamics (hulk smash versus kitty soft paws), this kid has electronic pads along with the acoustic stuff, this kid has glockenspiel for his drum solo, etc. I gotta place mics, set levels, set EQ, setting gates, fix adjust compressors, some of this only if there is even time. It can take a while to sort all that out. And then there are the potential issues, like awful tuning, ringing drums, rumbling drums, non-ported kicks, etc.
Bass, let's see, I grab an uneffected DI line through my box, tweak the compression on the board, if necessary (set around 8:1), get the incoming volume to match what you usually have so the threshold kicks in as per usual, tweak the high pass to clean out mud, if necessary, and try to match what is coming from the amp with a some eq. I can usually get a solid tone from the DI in less than 5 minutes. Often much less.
If there was equal time spent, let's say 15 minutes on each, I could really get the bass sounding exactly the way you want it, and I could do it in a way you approve, and then I could not get to half the show stopping craptastophe that is coming off the dam drumkit, if things go wrong.
And yes, having the singer sound good, both FOH and on stage, is my priority one. Then comes making sure there is no deafening feedback, from mics or acousitcs or whatevers. Then comes no phantom rumblings / ringings / loud buzzes, which usually come from drumkits and guitar rigs that didn't get sorted out / sounding good. These things are total audience distractions. Then comes a solid overall mix, of which bass is an equal part.
I love bass. But as a soundman, my philosophy is: serve the check writer first, the audience second, the band third, me fourth. Simple as that.
SEXUAL CHOCOLATE! </drops mic, walks off stage>