Platinum, palladium and platinum/palladium prints can have a long smooth tonal scale, and with the right negative are really beautiful. When done right, it's also one of the most archival processes.

6x6cm contact prints can be like little jewels, so I wouldn't rule them out.

The basic way to make an enlarged negative with an enlarger is to make an interpositive on ortho film like Ilford Ortho Plus, which can be handled under safelight, and then contact the interpositive to another sheet of the same film to make the internegative--an involved process, but when it all works, it's worth it.