GOOD PARALLAX MAPPER WANTED

I've been working on designing a game in RMVXA for the better part of three years now and in terms of story, it's completed. What I need, however, is someone to make attractive maps for me. Here's some more info on the game itself and what this job would entail:

The game is called Cinericus. It takes place in an entirely original world with spanning and developed myths, lore, etc. This game in particular (though more taking place in this world are possible in the future) focuses on the power struggle between two nations, one of which is populated by humans and the other by beastmen. The main characters are three beastmen who found themselves as enemies of both their home nation and the nation of humans that wants them dead, and so they flee to lands that for the better part of fifty years have been thought barren. From there, the plot unfurls as all of the secrets behind villain's motives become known, as well as the knowledge of just how real the gods are.

So here's what I need from somebody who would be willing to take this job:
-obviously since I'm requesting Parallax Mapping, you should probably already have Photoshop/Gimp/whatever.
-I have a list of free-to-use resources bookmarked that I'd like you to use (more information can be provided if requested).
-You actually will not have to design an overworld. The players will not at any point have to walk across any of the three main continents in an overworld-y way. You will however, as the most major things you will have to do, design three very large cities, a sewer system (does not have to be very large), a fair amount of smaller, less-important towns (I'm estimating 10-15), one massive dead/ruined forest scenario, one large ruined city, a pretty large number of random dungeons (thematically varying--for the most part ruins, castles, cave systems, etc.) and heaven (Caelus) and hell (Ad).

Anybody who takes this job will be given full credit for their effort in both the opening and closing credits. This is not a commercial game, therefore payment will not be initially given to volunteers. However, upon the release of the game, a paypal account will be set up where supporters of the game can donate. Profits will be shared equally among all people involved in the game (currently this is two: myself and a composer).

Things this game already has (to seem more credible for those of you on the fence):
-a completely finished storyline, down to every detail--characters, events, etc. all done.
-developed lore and mythos--every nation's history is large and spanning and makes the country overall seem very realistic.
-developed characters--similar to above, all of the characters have been carefully thought out and planned to make for enjoyable characters. Any player could find at least one that they empathize with or relate to.
-a nearly completed soundtrack. Yes, the entire soundtrack of this game is done, aside from songs for the opening and closing credits.
-many unique mechanics that make it feel like a fresh new take on the classic turn based RPG.

What this game still lacks:
-maps (this is where you come in!)
-some sprites (I am designing these)
-some faces (also designing these)
-a few other miscellaneous graphics that the game can survive without until further notice.

So, if you're interested, reply here or message me for more details. As well, I should clarify that if multiple people would like to collaborate on this project, I am all for that. However, know that whether it's one person or three people, you all must have some degree of flexibility with what I'm looking for in this game.
Thanks in advance!

In this case I'm willing to use whichever the mapper is the most comfortable with--I want to make that job as simple for them as I can. Also, my experience in parallax mapping is minimal, so I'm equally willing to listen to the mapper's recommendation of which is easiest to use for me. As far as Gimp, I do already own it so no worries there.
For further info, the graphics I will be primarily using will be those found in this thread (obviously with appropriate credit given to the creator). Many examples of maps made with these tiles appear throughout the thread and the style I'm going for is something for similar to that because frankly those maps are beautiful. Just to clarify in case you're unsure of whether or not you're capable of doing what I'm asking.
And the thing is, I will give you detailed descriptions of maps you need to make, where you come in is basically making it a reality and peppering it up with just visually stimulating things here and there so that not every map is an expanse of one kind of land.

Yeah, the underwater structures seem kind of superfluous to me so that's a level of detail that I'm probably going to not expect of an artist. The above-water is what drew me to this, and that seems (at first glance) to be a matter of tile mapping as in the engine, but just with many additional details that the engine does not support. As far as the scripts go, I'm able to learn how and where to use them properly but I figured I would get a mapper's opinion before committing myself to a certain way of doing things.