It's complex problem, so it's pretty much impossible to make an accurate assessment without actually being in the room.
Worship halls tend to be big boomy spaces. This makes it very difficult to deliver a good bass sound and it also make it difficult for the bassist to hear. Since the bass builds up and sounds bad, people tend perceive it as too loud.
My approach: I elevate my amp and tilt it back to aim at my head. This reduces coupling with the floor and puts a dip in the low mids that I like. It also ensures the the full frequency range of the cab travels directly to my ears. The key here is this approach increases the ratio between direct sound which is clear, and indirect sound which is diffuse and incoherent.
Caveats to my approach: In really bad acoustic spaces, it's still hard to hear as well as I like. If you like a deeper thumpy sound, you will hate this approach.
Something that compounds the problem is most people want about 6-10dB "more me." In small spaces it can be difficult to get the desired 6-10db of more me because the distances between players and various sound sources is too small.
I will state this caveat. I am not an acoustic engineer, so the following may not about 100% technically correct. Hopefully it's close enough to help you.
The direct sound coming from you amp drops off at a rate of 6dB for each doubling of distance. Let's say you are 4 feet from your speaker and it is producing 90dB at 3'. At 4' the SPL is 10Log(3/4) + 90 = 88.75dB. I.E. the sound dropped off 1.25dB after travel from 3' to 4'.
Let's assumed the guitarist is 12' from you cab. The bass SPL he hears is 10Log(3/12) + 90 = ~84dB. In order for the guitarist to get the desired level of more me, the guitar's SPL must be 6-10db louder, or 90 to 94dB at his/her ears.
Let's assume the guitarist is also 4' from his/her cab and you are 12' from his/her cab. This means at 3' from the guitar cab, the SPL is 91.25 to 95.25. Let's assume the guitarist is set to 93.25dB at 3", which is in the middle of the range. At your position the guitar will sound like 10Log(3/12) + 93.25 = 87.3dB.
So you are hearing 88.75dB of bass and 87.3dB of guitar. This means your only getting 1.45dB of more me, which is probably way less than you want.
The more me issue is even worse in a big boomy hall because the sound builds up and bounces around. Under this condition the sound is smeared and diffuse, and the SPL is the same throughout the reverberant field. Keep in mind, the direct sound coming from your amp is louder close to the amp and drops off with distance. So at some point, the indirect sound which is the same SPL throughout the reverberant field can actually be louder than the direct sound you hear coming from your amp. It can be really hard to hear the bass clearly even when playing by yourself.