Created naval line of techs from Ancient era to Renaissance. This way land locked civs don't require naval techs until the Industrial era.
Created tech line for air units from Modern era to Information era so that some progression can be made without being forced to research air force techs right away. All techs are still required to finish tech tree.
Rearranged some techs in the Atomic era and Information era and added more prerequisite connections to slow down progression.