exploring mini bass amp as a possible project

I've gotten favourable response to my McGrath Mini guitar amp, recently completed.  One fellow inquired whether I could build a similar mini bass amp.  Well, honestly, I don't know if I can or not!  Superficially, this would seem to be a similar project, but in all the details, I think the requirements to be useful as a bass amp are significantly different.

Certainly, I believe a bass amp will need more power, and a bigger speaker.  How much more and bigger?  Therein lie important questions.

Also, the circuitry must obviously be tuned to pass lower frequencies.

Rather than start designing from first principles, I'm starting by looking at what I consider to be a promising model: the Ampeg B15N.

These amps have evolved over the years; I found a relatively recent schematic (as evidenced by fixed-bias, 5AR4 rectifier, and "ultra low" and "ultra high" switches).

So my thought is, maybe base the design on this, except only one channel, 12AX7s instead of 6SL7s, EL84s instead of 6L6s, and cathode bias.  Hopefully I can use one of the Chinese switching power supplies.

So then there's the question of speaker.  I feel like closed-back cabinet will be necessary, and maybe something like a 10" speaker.  The overall cabinet dimensions might not need to be that much larger than the McGrath Mini guitar amp.  But a bit larger.  Maybe 12" x 12", and 7.25" deep?

I think no fx loop, etc.; however, in place of Ampeg's "ext amp" jack, maybe it should have a transformer-balanced XLR, as well as unbalanced 1/4", with a level control ("direct out").