It would be great to set to "random" some values in a ruleset, especially in geology and sociology, but even in the tech tree, just for the purpose of giving some surprise.
However, it would be not a surprise if players can actually see these values in the server settings window, or infere them from the client.
To obscure settings from the client may be hard to achieve, but I bet that it would be quite easy to keep a random value secret, just as the generator seed is. If we can't infere it from the client, here you are a random misterious value.
For values which can be other than "off" or "on", randomness could be limited to a previously chosen range.
Speaking of the planetology/geology settings (which are the most obvious and simple settings which may receive benefit from randomness and mistery), there are some values which cannot be infered at the beginning of the game, or even later, e.g.
- Landmass. To avoid having too much or too few tiles per player, we can give a small range variation, such +- 20%. This would be enough to let indetermined if a world would be mostly oceanic or not.
- amounts of hills, heat, water, specials. Are all those mountains and rivers a common feature of this World or is it just the characteristic of this corner of the island? Only further exploration can confirm.
- 1x1 islands, poles, temperate.
- Generator and players placement. This would be a very radical randomness. In most cases players can infere them from the 1st 10 or 20 turns, but if mixed with other random values, it could be much harder to infere, and much intriguing to play.
In order to achieve more mistery, it would be important to abolish the sea order recognition (Ctrl+centerclick).