In this forum, a number of projects with PCBs to go with them are presented. Some boards are more universal that others like the Clementine. That is good if someone wants to try something else that 1626.
I recently obtained a slightly similar universal PCB for KT88, but also tubes like 6L6 and even GU50. However the board is buggy and needs to be corrected in some places.
Not long ago, I saw a universal driver PCB with a compactron triple triode, set up for a PP-amp driving a pair of whatever, pentodes, tetrodes, triodes. Think it was one of Pete Millets inventions.
I would like to see more of that, universal driver boards for SE and PP amps, not a complete amp. It could definitely be of help when breadboardning new stuff.