I think you are heading in the right direction with your little fly rig

. Hopefully you get to work with some audio tech who have time and interest for a short conversation, so you can explain you sound concept. If you work with the same person regularly you might also provide and talk over some recordings, but make sure the recordings actually represent something consistent. A lot of times people provide examples of what they like and each example is significantly different from the other, so it's hard to understand exactly what they are trying to communicate.
Ultimately I think you should try to communicate, but in the end you have to just go with the flow unless you have the power necessary to call the shots. So don't stress over it too much.
If you are super concerned about what you hear in your IEMs, build some sort of personal monitor rig that gives you more control over you personal mix. A rolls PM351 may do the job, or you may need to get a small mixer and a mic splitter like a Radial JS3 if you sing. The mic splitter does the same thing for your mic as a DI does for you bass. The idea is you signals goes to 2 locations: 1. FOH, 2. your small mixer.
With a small mixer, a DI, and a mic splitter, you can take a stereo IEM feed from the main mixing console, and you have local control over your signals (bass and vocal).
As you probably know, some of the digital consoles can be setup so you can control you IEM mix wirelessly with phone or iPad.
One thing that I have thought about mentioning but never did. You can not judge how you sound in the house from the stage. Keep in mind that low frequencies are omni-directional so you will hear a lot of sub-bass coming back from the subwoofer. Higher frequencies tend to shoot straight out instead of wrapping around the cab like lows. So if you hear the mids and highs, it will be after they have bounced off the back wall and come back at the stage. Due the distance the sound sound must travel, there will be a time delay and SPL decreases 6dB with each doubling of distance, so the balance between sub-bass and the higher frequencies will be off.