I really like the idea of boss monsters from the resurrection campaign, as it adds a neat little mix up to the usual ADOM crawling. In my last play through, however, I only encountered one boss monster through the ENTIRE game (and that was when I was backtracking through a dungeon). I feel this is a feature that has not been fully utilized, and I think it would be cool to be able to adjust the chances of them spawning. The options could be similar to how treasure changes and monster difficulty are utilized when making a new character.

For boss monsters, perhaps the options could be: None, Few, Standard, Many.
I would think the "Many" option should give a good chance of seeing them more often.

In a similar vein, we could also do the same thing for the statue dungeon feature. That could also have a "None, Few, Standard and Many" option.

I know how some people hate having two RFE ideas in one RFE, but I felt the idea is similar enough for both of these that it was alright to make one.