The eureka system is still more creative than the set in stone tech orders in civ5 and especially civ4. People wailing about getting them too easily might want to up the difficulty. A lot of them are situational, depending on whether you have a specific resource, and many are far harder on higher difficulties. Make chopping lose the overflow if used for a different purpose. Buff Great Library, it is useless now. Techs and civics come too fast.