Wow... this poll is just taylor-made for the
Wolfshanze Mod.
If a Str-8 wooden-hulled Frigate, jumping to a Str-30 Destroyer bothers you in any way shape or form, then you need the Wolfshanze Mod now.
The same thing bothered me immensley... yes, there's a huge jump and time disparity between the ocean-going Str-8 Frigate and the WWII era Str-30 Destroyer (which comes near the time of the Str-40 WWII Battleship). Yes, there's the mostly-worthless Str-12 Ironclad, but let's remember it's a coastal-only gunboat of little value since it's both slow and heavily restricted to coastal waters...
So what you get in default Civ4 for ocean going vessels is a Str-8 Frigate, which rules the waves for countless eons it seems, till it's replaced by modern destroyers? WTF is that? Let's not forget transports are a little funny too... going from Spanish Galleons to modern WWII Higgens boat transports? Nothing inbetween?
In my
Wolfshanze Mod that was the main purpose that I set out to fix.
I categorized naval eras and setup up very specific timeframes with (essentially) one light/fast unit and one slow/heavy unit for each timeframe (think Frigate/SotL or Destroyer/Battleship for my reasoning... keeping it close in-spirit to what Firaxis was doing).
After Frigates, Ships of the Line and Galleons, this is what I did:
Age of Steam:
Ironclad Gunboat (same as default Ironclad... coastal only)
Ironclad Cruiser (ocean going... light/fast)
Ironclad Battleship (ocean going... heavy/slow)
Paddle Steamer (Age of Steam transport)
Industrial Age:
Protected Cruiser (light/fast)
Pre-Dreadnought (heavy/slow)
Transport (now Liberty Class vessel)
WWI era:
Destroyer Escort (light/fast)
Dreadnought (heavy/slow)
Getting back to default Civ4, you then finally progress to what we already have...
WWII era:
Destroyer (light/fast)
Battleship (heavy/slow)
Similar units of equal technology aren't artificially spaced-out either like they are in default Civ4... the same technology makes both destroyers and battleships but they are greatly spaced on the Civ4 tech tree... that's simply not right... in the Wolfshane Mod, once you reach the right requirements for a certain level of naval warfare, you get the heavy and light versions at the same time.
As one last naval tweak, Submarines now come with Combustion + Electricity... the two main forms of early submarine propulsion, and makes the sub available a little earlier then default Civ4... also the ability to carry missiles has been removed from the world-war era sub and transfered to the nuclear powered "Boomer" subs which come later on the tech tree.
If the huge gap in naval techs bothers you, that was the focus of my fix in my
Wolfshanze Mod.