anyone who remembers my post from a few weeks ago about recording drums may recall that I'm in a band and our drummer LOVES drum mics.
He has a huge set, but his playing isn't super loud (hes not smashing the heads, just hitting them)

usually when we play shows, which are usually in smallish venues and places like large function halls, etc., he often has a few drum mics set up going into the mixer. my question is, at what point (i assume this decision would be based on the size of the room), is it a good idea to actually send these mics with any perceptible level to the main speakers?

is it a good idea to generally do this at low levels even in small venues, to allow you to control the relative volume of the drums more?

our setup by the way is:

2 guitar amps>SM57 mics>PV20 mixer
Bass guitar > PV20 (DI)
Keyboard > PV20 (DI)
Vocals and backup vox > SM58 mics > PV20
the PV20 goes to i think a Beringher EP2500 PA, which goes to 2 600-watt each Harbinger speakers, i think they are 2x15 in, idk the size of the horn,
and also we just added another 400-watt Peavey speaker
these are all on one channel of the EP2500, and the other channel (at a significantly lower level) goes to 2 or 3 small (75-100 watt) monitors.

I see these drum mics as an unnecessary hassle but is there a reason one would want them if the drums are pretty loud anyway, since we're playing in small venues?

oh and by the way, if it changes anything, we dont have any compressors right now but I'm planning on picking up an inmexpensive 2-channel one, i was going to use it on lead vocals (i play guitar also and have pretty poor mic technique and want the vox to cut through) and bass guitar, but i could also use it to compress the whole mix?

thanks in advance!