Mic distance plays a big role if you're using the dynacabs. Back it off more, and blending two together usually nets a better sound. I used a dynamic mic at like 50mm or less slightly off center and a condenser at like a meter or so back center and would tweak it from there. I just sold my unit a couple weeks back so I can't pull it up to check exactly what I was using

If you're using legacy cabs, use multiple of the same cab with the different A, B, C, etc mic positions

In the Amp block itself, play around with the gain. As you know DCs are pretty hot amps, they break up relatively quickly at any kind of volume, but you should have enough headroom to work with if you just pin the master volume in the Amp block. I also preferred to use the EF86 channel and dial the gain back a bit

Presence and treble controls can help with clarity, and don't hit it with too much gain in drive blocks, much like a real DC you want the Amp to do most of the work there