For me I would like to see:
Active and Passive separate input sockets,
Gain - Mild break up from half way onwards,
Bass,
Middle,
Treble,
Master Volume,
Power Scaling knob (a la Marshall AFD100/London Power. See: [url="http://www.londonpower.com/london_power_technologies.htm"]HERE[/url])
200 Watts Power stage,
2 x Speakon outputs,
2/4/8 Ohm Switch,
FX Loop with Level control pot,
XLR D.I. out with a Pre/Post swtch & a level control,
Auto Bias circuitry (a la Marshall AFD100 amp),
The Power Scaling would cover the requirements for lower volume with all the valve sound for recording/small gigs, etc.
edit:Spelling & forgot the D.I. out!