Johnny
I meant realistic in the sense of full detail, terrain, weather, etc. I think units and unit movements should have some semblance of reality, which, as I noted, Tim's research confirmed. I wouldn't want to create "bullet" ships just to make the action more intense.
The ship speed also forces additional strategy into the game.
I could see the argument that sea units are too weak and vulnerable, though.
Its not realistic though. Tim's research confirms speeds in a vacuum, not under real conditions. Please refer to historically rapid advances rather than mere mph and you'll see what I mean.
Also, ship speed doesn't force either more or less strategy. Strategy adapts to the rules, unless by more you mean more cumbersome, as in the cumbersome fleet that you had to create to cross Ankylo. Faster ships allows lighting strikes like the vikings of yore. Its hard enough to sneak up on anyone in this game because the color of the terrain changes when you take it. The sea is the one place where you can "sneak up". (Sidebar: I was opposed to radar for this reason).
Without the ability to achieve surprise, the warfare become largely economic as the larger power crushes the smaller by shear weight. In my view, a smaller power should be able to land a seaborne raiding party and seize a capital, thereby cutting the larger foe in half in a single blow and evening the odds. Of course, to do this, not only would ships have to be faster (as is reasonable), you would also have to have the option to move forces without occupying territory and thereby changing the color of the turf. Not only would this allow tactical or strategic surprise, but it would allow allies to aid one another without being confined largely to the use of airpower only.