First, make sure that your PA speakers are in front of the stage and that all mics are behind the speakers.

Are you using a stage monitor so you can hear? can you control the volume of the monitor separately from the PA mix? Are you putting the monitor in the null point of the mic? (Probably not with the C1, since the null point is straight back from the center).

Working "old timey style" take a lot of coordination and choreography. And significant musicianship to balance the dobro and banjo (which are loud) against the guitar and bbutt and vocals.

If you want to try separate mics, look up "close mic techniques" on the 'net. You really want mics with good rejection, more so than you'll get with standard cardiods like the Shure SM57 and SM58s (which are essentially the same mic internally).

You will have better luck with "hypercardiod" pattern mics, such as the BeyerDymanics M201, Electro-Voice N-D 468 or a Neumann KMS-105 hypercardiod vocal mic. The N-D 468 is very handy because it has a swivel head, and can point down into a mandolin.

Of course, with all the mics, you need cables, stands, and a mixer. And realistically, you will need someone to run the mixer, as you can't play and listen and adjust all at once.