Just looking for a bit of advice with acoustic volume when playing with a group.

Started attending Folk sessions near me after a guy I met recommended them. I'm not in to Folk, but it's the first time in 12 years of playing I've actually been able to play with anyone. Anyway..

I've generally been taking either my 12-string or resonator since they are strictly acoustic only events, but as soon as any song starts I can't hear a thing I'm playing unless I really just hammer chords as hard as I possible can. The venues are usually fairly small (Pubs mostly) and the groups vary in number from anywhere between 5 and 15 other players, but even when the number dwindle and I've played with as few as 2 or 3 others I'm still inaudible to the point that people have commented on the lack of volume/"tone".

When I first started going, my 12 string bridge was lifting which I got repaired in the hopes it would improve which it didn't. I've tried new strings, different gauges, different tunings in the hopes that the different ranges might cut through more. Doesn't really seem to have helped.

Is there anything else that I could realistically do with what I've got to change anything? Failing that, are there any specific traits in a new guitar (should it come to that) that I should look for? So wood types, string types, body construction and the like. I'd try more at local music shops, but the area where I live seem to only sell fairly low tier brands, all of which I have tried with basically the same result.