VIP
As you Know, I am hard headed sometimes
But I also gotta say that this forum does not like Cartoony HDRs. I am starting to not like them less myself. so I am trying to make a natural style and workflow.
i am on the right track. I am going to redo my trackers. and I will post the new results this weekend.
Thanks.
Some of the HDR here fanbois do... but
I don't.

I get bashed for my comments on HDRs all the time, but this might be a case where I can don my cape and actually have someone not be ticked off.
First off, I think your image is really very good from a "trying to make it realistic" standpoint. To my eye it was clearly an HDR, but like someone else said- us photographers are used to seeing them so we know. That said, I
have seen HDRs on here that I didn't realize were HDRs right away, so it's possible you can take this further.
What I noticed about it was that the contrast and saturation were still on the high side. It particularly stood out for me in the texture of the paint/dirt/whatever right there on the nose. I tweaked it a bit in photoshop and noticed that if I pulled those down that it stealthed its HDR nature just a little better. You may want to mask out the sky and just do the train when you do this.
If you decide to do this, I think it needs to be VERY surgical. The textures and such that you see are interesting, and contrasty images (IMO) are very pleasing. You don't want to wind up with something that looks flat and dull, realistic or no.
Anyway, might be worth a try, but again... very nice treatment even as it is.