There are things you can do to slow down bots and scripts, true, but more than that I think there are ways to keep aggressive scripters from playing on your server all together. We pretty much all share a common theme in things we like, and if a server goes too far from that most of us won't bother playing it out.

In an unlim game, move and steal delay do this. Don't go too far with it, but while the combination of both does make scripts more powerful... very few aggressive unlim players will want to deal with them at all. The same is not true in a turns game, however.

In a turns game, slow down planet development and make ships more expensive but less powerful. Make sure attack odds and def odds are balanced on the big. Also bring up the cost of gtorps to max and reduce the corp size to somethin small like 2 or 3. If you really want to drag things out, make the uni a 20k and keep the turn base under 1k. Most scripters will not find a game like that fun.

LOL, and get all of 3 players?