David:
Hey! COOL! Welcome to the world of slightly rough east-block renditions of the oh-so-diverse re-used Renault UE!
I'm a fan of the general type - and have done a few of the Mirage/RPM kits (those with the wurframen, and a base model), and I just picked up the kit with the 3.7cm PaK 35/36 gun mounted on it. These kits are all pretty much the same - and they are pretty far removed from the Tamiya version. But I found them actually in some ways pretty good.
It's apparent that you did some homework and accessed some reference pics. All power to you! What I might suggest is that you study a few pics of the general type, and maybe choose a few bits to tweak. I found it pretty enhancing to add a few of the tiny and tinny details around the box, and I replace the tow cable with a wire one with some little metal or styrene clips for holding it onto the front deck. This could be the single biggest boost for the least effort. That, and the heat shield over the exhaust- it was a tinny piece and the kit part looks much better if you seriously thin the visible edges, and do a little scoring with your X-acto tip to create some depth under those pressed-out cooling slots. Check ref pics and note that many panels appear to have distinct thin gaps and seam-lines around them- I found that scoring these and pin-washing made it pop a little more.
The hands-down fiddliest part of these little kits is the track
They are rather crappy. When you hit those tracks... the length bits are OK - the links are really tiny and don't have much positive connection when you assemble them 
.... I found that things worked best to fit the painted road gear on, including the sprocket, and then assemble a short run of links for that sprocket by setting the links onto a piece of masking tape (stick them on face down) and applying a little thin cement to the run - let it set several minutes, and then gently lift it off the tape and fit it around the sprocket. As I like to paint my track off the tank, what I did was to do this set-up, let the run harden in place, and then pull it off the sprocket and let it fully dry. I painted all the lengths and a run for the idler and the sprocket each side, and then re-set them onto the running gear using some super glue. I had to do a tiny amount of touch-up painting to cover the glue, but it worked pretty well. Do take care and look at the attached track runs from front and back... these little tracks do like to twist and tilt, and that is fatal if you put it on a show table! I been there
NO T-shirt resulted, either.
The decals are OK - but I pretty much skip those things in favor of spraying crosses on with a template. But that's me.
When you get paint on, maybe keep in mind that these were rear-area airfield vehicles and probably did not have great paint-jobs...!
I look forward to seeing it all done and posted! Again, COOL and really nice to see someone else getting into these strange but actually fairly common little vehicles!
Bob