Plasmatech,
I'd agree with you towards tubes simply because tubes are easier to get vs. vintage quality transistors that may be longlong time out of production(in case if they're blown). NTE equivalents often don't match parameters and don't fit onto the designated slots. In this case you'd have to re-engineer, re-drill heatsinks and mounts and if they run hotter vs. original yo'll even have to either increase heatsink surface or build a fan.
As to circuit boards there are vintage tube amps that have circuit boards as well.
As to sonics, I love sound of vintage solid states especially Sansui and Accuphase.