Many of these drawings were commissioned by Allen Knott for his Battlestar Leonidas fan fiction. Many appear in his story under different names, especially the Raiders. Information can be found at the Galactica fanon wiki. I haven't put designs here that are exlusive to any partitcular fan fiction. Those are on their own dedicated pages.
Tiger Class Destroyer Mark II
Apollo Class Corvette Mark II
Cheetah Class Light Cruiser Mark II
Apollo Class Corvette Mark III
Steyr Class Frigate
Hyperion Bay Class Heavy Cruiser Mark I-Refit
Nebulon Class Frigate
Hyperion Bay Class Heavy Cruiser Mark II
PC 109 Class Patrol Craft
PC 001 Class Patrol Craft
Nebraska Class Destroyer
Ovidius Class Light Battlestar
Camelot Class Research, Shipyard, and Space Station Top Side
Athena Class Battlestar
Spartan Class Battlestar
Colossus Class Heavy Battlestar A semi-canon design based on the large Galactica-style ship seen in Razor at the Scorpio Shipyards. It was probably a CGI error, the Shipyard scene was riddled with them.
Apache Class Fleet Tug
Yorktown Class Carrier
Stalingrad Class Carrier
The original Twelve Battlestars: Columbia, Galactica, Atlantia, Rycon, Prometheus, Cerberus, Pacifica, Solaria, Triton, Pegasus, Athena,
Fighters and Small Craft
Apache Class Raptor Mark II
Apache Class Raptor Mark III Based on a concept sketch for the planned "Blood & Chrome" series.
Apache Class Raptor Mark IVA
Apache Class Raptor Mark IVB
Apache Class Raptor Mark VA
Apache Class Raptor Mark VB
Starhound Class Stealth Viper Mark I
Starhound Class Stealth Viper Mark II
Starhound Class Stealth Viper Mark III
Starhound Class Viper Mark VIIIB Marathon
Starhound Class Viper Mark VIIID Marathon II
Starhound Class Viper Mark VIIIC Sidewinder
Starhound Class Viper Mark IX Pilum
NON colonial designs
Designs belonging to the Eastern and Western Alliances and Earth.
Chameleon Class Medium Cruiser: Based on the Whitestar Class Medium Cruiser from Babylon 5, this is an Earth ship in the Leonidas universe.
Stasi Class Gunship An Eastern Alliance gunship.
Cylon Draugr Class Destroyer
Cylon Revenant Class Heavy Cruiser
Cylon Styx Class Escort Basestar
Cylon Duzakh Class Basestar Mark II
Cylon Diyu Class Light Basestar
Cylon Barzakh Class Heavy Basestar
Cylon Invader Class Drop Ship Based on a design by Todd Boyce of Battle Spoo.
Cylon Violator Class Landing Ship Based on a design by Todd Boyce of Battle Spoo.
Cylon Predator Class Landing Ship Based on a design by Atolm
Cylon Tartarus Class Gunstar
Cylon Uranus Class Strikestar
Cylon Wraith Class Frigate
Cylon Oliphoth Class Corvette
Iblis Class Basestar Based on a design by Atolm
fighters and small craft
Cylon Heavy Raider Mark I
Cylon AB Raider The Galactica 1980 design upgraded to the new universe.
Cylon Stalker Class Stealth Heavy Raider
Cylon Stealth Raider Mark I
Cylon Stealth Raider Mark IIA
Cylon Stealth Raider Mark IIB
Cylon Raider Mark VIII: Imperium Class Raider
Cylon Centurion Model 003
Cylon Centurion Model 004
Cylon Centurion Model 005R A lightweight reconnisance model
Cylon Centurion Model 005CM A heavily armed assault Centurion.
Cylon Centurion Model 008C A command version of the new series Centurion.
Cylon Annihilator Class Centurion
Cylon Centurion Model 006: Interwar period design between the 005 and the 008
Cylon Centurion Model 007: The immediate predecessor of the Second Cylon War Centurion. It was more independently minded, not having been modified by Cavil.