We are working on a renovation project in Södermalm, Stockholm. It is an attic apartment built in the 1980s. The ceiling was lowered and it didn't have the attic feel. We have now opened it up as much as possible, including exposing the beams. These are "mistreated" to fit the previously plastered inner ceiling. My question is whether there is a gentle and good way to restore beams from the 1880s? Some suggest wood filler and staining. Some suggest enclosing them. I would like to have a complete beam structure if possible. In the worst case, it will have a "patched" look. Grateful for suggestions.