Series of Starship Illustrations

I'm requiring some concept designs for some starships / spaceships for a Tabletop Role Playing game I'm developing. I'm looking a series of images, the final designs will either be an isometric (3/4) style image, or a combination of side image and top image. I have seven (7) different factions or groups, and require multiple images of each faction type of ship. Various sizes, from fighter sized craft to battleship / dreadnought sized vessels. Some initial mock ups are posted below in order to demonstrate the feel of what I'm trying to achieve. Further details are contained in the draft contract that the successful applicant will be required to electronically sign (ie agree to in writing) before commencement, as well as a style guide that will be supplied. I encourage bidders with questions, concerns or ideas to discuss to contact me via the messaging system so that accurate and developed proposals are possible. Note that time is not a significant factor, I will however hold bidders accountable to their submitted deadlines, so honesty is appreciated. Portfolios of similar work are helpful, not essential. Here's a list of what I'm looking for (note stretch requirements are included to separate bidders that wish to include them in their proposal, however no stretch requirement is mandatory): A) House Amberes 1) A fighter sized multirole vessel, ala Raptor from Battlestar Galactica or Dropship from Aliens 2) A Cruiser sized warship, visually similar to current sea going vessels. Prominent superstructure towards the aft. i) Stretch requirement – A battleship / dreadnought sized warship, designed as a carrier command vessel B) The Bromley – Stone Consortium 1) A fighter sized shuttle craft that could be converted into a gunship, with rotating modules or moving parts 2) A Cruiser sized trading ship that could be converted into a warship, with rotating modules i) Stretch requirement – A small runabout / personal transport sized vessel C) The Tannatha Protectorate 1) A sleek fighter sized craft, very curved in appearance 2) A Battleship / Dreadnought sized warship, very curved and sleek in appearance i) Stretch requirement – A corvette / frigate sized warship, very curved and sleek in appearance. D) House Karrow 1) A Cruiser sized warship with large bull shaped forecastle, with significant wear E) The Obsidian Group 1) A fighter sized biological ship, looking like a space tick or some sort of insect 2) A Cruiser sized biological warship, an evolution from the fighter sized craft with ranged weapons. i) Stretch requirement – A dreadnought sized biological warship, again evolved from the cruiser sized vessel. F) The Sierra Collective 1) A small fighter sized vessel, with sharp lines and mathematically alien styling 2) A dreadnought / battleship sized vessel, with sharp lines and mathematically alien styling i) Stretch requirement – A corvette / frigate sized warship, with sharp lines and mathematically alien styling G) The Akeema Fleets 1) A cruiser sized vessel, salvaged from various parts of other vessels (Bromley Stone, Amberes, Karrow). Old, battle damaged, worn but treasured. i) Stretch requirement – A fighter sized vessel, salvaged from various parts of other vessels (Bromley Stone, Amberes, Karrow). Old, battle damaged, worn but treasured. H) The Holy Order of Dominus 1) A dreadnought / battleship style vessel, a holy relic and one of a kind vessel, shaped in the Symbol of the Holy Order, gleaming and revered.