There are many things to like about the HHKB Pro 2, including the 60% form factor, unique yet intuitive and efficient layout, dye-sublimated PBT keycaps, symmetry, and overall styling elegance. However, after using mine for several months, I felt that I still had not found the right sound and feel, and I started to be bothered by the "clack" sound on the return stroke of the keys.
Recently, I have rediscovered IBM Model F keyboards, including the XT, AT, and 122-key Model F. These boards use capacitive buckling spring switches as opposed to the membrane buckling spring switches employed by the Model M keyboards, including the 101-key, the SSK, and the 122-key Model M.
I am typing this with an IBM XT connected to my Mac with a Hagstrom converter box. I have remapped the keyboard to a HHKB/Mac layout. Now I am looking forward to doing an ANSI mod on my AT and 122-key Model F and installing Soarer's Converter in them.
Although my new favorite switch is the IBM capacitive buckling spring, I still prefer the form factor, layout, and appearance of the HHKB Pro 2. Now I think that the perfect keyboard would be a HHKB Pro 2 with a steel plate and IBM capacitive buckling spring switches.
However, to be more realistic, I think a near-perfect board would be the HHKB Pro 2 with silenced 55-gram Topre switches. This could be done by transplanting the domes from a RF 55-gram board to the HHKB Pro 2. Otherwise, for those who like the 45-gram weighting, the HHKB Type S is available.
Back to the IBM world, there was limited production of a HHKB-like Model F that has been dubbed the "Kishsaver". If I could find one of those, my keyboard odyssey might be over. For a while...