I've long held that bass guitar is the most difficult instrument (in a standard rock band format) to get to sound good and sit well in a live mix, both on stage and in the audience, whether the bass tone is being supported in the PA system or if only a stage rig carrying the room. Bass is a unique combination of tremendous dynamic range and broad frequency range. Context means EVERYTHING, and this is made more difficult in live settings depending on the room acoustics and stage/PA gear used.
I think the more successful live bass tones are derived from having a good understanding of the role of the bass within the group format, whatever that may be. If you're sounding more like YES or RUSH (bass is a featured instrument), then a mid-heavy tone with grind is exactly appropriate since excessive sub-low frequencies do nothing but create a muddy rumble beneath the notes you actually hear, which generally is undesirable. In this context, the prominent midrange content allows for more creative options in the tone since you can actually HEAR what the bass is doing much of the time. Have fun with this and go nuts!
OTOH, if you're generally in a pure "support" role, holding down the low end, locking rhythmically with the kick drum and leaving space for vocals and other instruments (which are creating the density of the mix), then a fairly garden variety, perhaps darker tone - which may even be an uninspired sounding tone in isolation - is entirely appropriate. This is not to lessen the value of the tone itself, but rather, in recognition of the bass instrument's limited SONIC role in a group context. In this case, timing, note selection, and creating simple-yet-elegant bass line compositions are far more important than laboring over a "signature" tone. I find that in these situations, the simplest of stage rigs and DI feeds to FOH is all that is needed, perhaps with the addition of some leveling compression.
So, in a nutshell, for bass parts that have lot of movement and latitude to move all around your neck, you'd be wise to consider using a HPF to reduce the rumble/mud. For support role bass tones, keep it simple, and make sure the mid/high end isn't stepping on the toes of other (treble) instruments, and create an otherwise very balanced, even tone, especially in the sub/low regions.
One final note: the simple dry/DI approach will really highlight the natural tone of your bass and electronics (pickups, tone controls, filters, etc.). You may want to spend some time auditioning basses for their inherent tone, and price point has NOTHING do do with whether a bass as a desirable or unique tone. I've heard some really great tones come out of $100 beginner basses (though quality of build, hardware, electronics, setup/intonation are a whole other matter).
