Updated the table on page 77 with two new pentode families:
6BJ6: pin-out as normal 6AK5 but not everything connected on the base if understand this right. 0.15 mA heater current. Hence you should be able to operate even EF91/92 setting as well as 2/7 strap. I haven't tested those. "The 6BJ6 is a variable μ RF pentode designed for broadcast radio receiver applications. A key feature is the modest heater power making it attractive for mobile applications" (National Valve Museum).
6BA6: I got a Shuguang 6K4 in my hands, which is basically a 6BA6 derivative. 0.3 mA heater current. The pin-out is that of 6AU6. The cut off is remote though. Funny enough, it even works with EF95 but obviously the recommended setting is 2/7 strap. Just very coarsely, the tube sounds fine.
Sorry, I didn't want to sound greedy but this spatial perception was what I particularly didn't like about the Mullard 6AQ4. It would be a straight rule out criteria for me. Thank you for your impressions and also AFB's, which described the triodes further.