[HBR] HBR form factor - "mods"

[Ian Wilson]

I posted a few questions about receivers on another list recently, but it
occurs to me that many HBR builders and prospective builders probably
have opinions on these topics also. Here's a subset of my questions
(the context is 3-30MHz tube-only receivers, primarily CW/SSB):
  - best AGC?
  - best front end at handling large adjacent interferers?
  - best product detector?

73, ian K3IMW