It is intentional.

As a general critique of your workflow, it seems you are going out of your way a lot for something you intend to remove.
The gradient shading could just as easily be a single color fill on each plane intended to show the general shape.  Many artists begin with a general shape and work detailing into their piece afterwards.
Lining out a shape filling it with gradient colors to help you determine form and then recoloring over the entire thing later when you associate a light source is a sort of
A>B>L>M>C approach.  (Again... it seems to be going out of the way.[a lot])

It's fine to say it's a WIP and avoid critical assessment of existing flaws, but it's a good way to learn.  The process itself is part of the art.  Refining technique as well as the end result is a great way to develop your abilities.

I dig robots.  Looking forward to seeing where it goes.   

Thanks for the ideas Wes.  When I said I haven't applied shadows, I meant any sort of cast shadows from the angle of the light.
They are still toying with the idea of how to apply their shadows and I haven't created any for the assets.  However, the point of giving the angled portions of the building some more highlighting and shadows is a great idea.

I have done this and edited the poor stones on the parapet that were so out of whack.  I kept the shaded side a bit subtle.  Is that not enough?
Also I have addressed the tiling in the grass to give it a bit more of a randomized look.  Created with 4 grass tiles arranged randomly.

I will add shadow casting under some of the objects  and perhaps expand the building itself outward with some more features. I want to put a shingled type of roofing on the uppermost steeples.  Perhaps some sort of baked slate.  The perspective and angles may prove to be a challenge for me.

Picked up this project that had been started and dropped by a previous artist.  The tiles used are mostly mine. All except for the plants (trees, bushes, and flowers). These plants I have edited with some revisions to keep them more in line with the direction I took the project as a whole.

The owner of the project is rather pleased with the assets I have provided but I am in no doubt that it can all be improved and taken to new levels.
I would really appreciate advice and general critique on anything and everything which I can improve on so I can grow with this.  Hoping to push my ability further.

Note:  I'm aware that the bricks on the curve portion of the parapet need some work.  I haven't filled their angle outward to maintain their shape.  Also no shadows on this mock-up as there has been no determination for how shadows are to be done in the game he is making.

Reference:  My old link is broken. http://blognostics.net/wp-content/uploads/2011/09/animal-tortoise-turtle-ucumari.jpg
Finally got some time to work on an edit of this guy.
Been looking at it daily, agonizing over what to do with it.
Started by reshaping the head some and hacking off that horrible undercarriage that looked pasted in.
Applied a brighter highlight to the top and focused on capturing some of that glare that is in the reference.
Shaping and defining.  Worked with the colors to push the grooves and creases in and bring the raised portions out more.
Tried to rework the eyes so that they were angled back more and further up on the head.  Feel like the right eye (its left) needs more angling attention.
Raised the nose.

It looks a bit shorter than the other one (chin/neck is missing) but the shape is more correct and I am applying detailing to both sides rather than mirroring.

Now for the critique part.  Better?
Anatomy is closer for sure.
The nose.  Can I capture this brown/pink look or should I make it a light blue on the pink portion?  It contrasts heavily with the scale colors and I'm still no master at bridging colors well.

The neck.  I tried it again but scrapped it.  This is hard.  Any thoughts on this?  On the reference it's a kind of fleshy white/pink that hangs down and is stretchy.  Aside from the color change it's difficult to go from the chin which is very dark because of hard scales to this other surface which is a brighter color.
When I try as on the first version it begins to look like it is not part of the same as if it were glued on like a sticky beard.

Appreciate any feedback.

Thank you so much for the edit.
In the beginning this was a 1hr challenge.  You are quite right that I began detailing before I had the form down.  I started with an eyeball and worked from there creating the entire form at the detail level as I went. The chin was the worst part previously as I was using another color type for it and it looked REALLY flat and out of place.

Definitely going to give your suggestions a run, since yours looks a lot more like an actual tortoise and mine looks like some weird tortoise/frog sprite with a poofy neck.