Wouldn't that prevent generation of any civilisations whatsoever? And I should have been more specific, the problem isn't the savagery, that's all over the place. The evil, on the other hand, is rather more limited, and on my last few gens seems to want to stay in the mountains for some reason(??). I also occasionally get sites that look somewhat OK, for example the last gen had one that was tundra, but it was freezing rather than cold and had an aquifer. While the aquifer could make up for the lack of a river, I don't think I could cope with working around one and fight off terrifying creatures. I think I'll try a fortress in a more normal climate while until I figure out how to fix it.
EDIT: Wow, ninja'd. That's a good idea about freezing, I thought of setting temp!min to prevent generation of freezing biomes, but didn't know what this setting would be, and it didn't occur to me to test it like you say. I generally prefer not to cheat in games, but to get rid of the aquifers I may make an exception. I'll just have to remember to revert it if I feel like trying one as a challenge. BTW, I can't set higher minimums for evil zones, that's the max the game can handle. Putting it higher results in it being ignored, as I found out by increasing it beyond the maximum in notepad. When I realised, I fixed it and suddenly my map got a whole lot more purple. Thanks for the help anyway, I'll try this out and see if I can get it right this time.