Don't settle for the speaker model that defaults for each amp, experiment. Some of the speaker models seem really compressed and exaggerated to my ears. I like the tweed 1x12, it seems more dynamic and realistic/neutral to me. I have also noticed how much different this thing can sound thru various headphones, and hi-fi amplification systems, a patch that sounds lifeless or bass heavy ( or exaggerated) in one context, may sound great in another...It does sound surprisingly good when recorded and played back on my computer's SB.
Also, if you haven't done so yet I would update the firmware to version 2.0, Johnson has added 6 new amp and 7 cabinet models; one of my favorites is the new '65 Bassman with the tweed 1x12