Thank you for the kind words! I didn't expect to meet such an enthusiastic dinosaur expert here. :D
When I have the time I will make those alterations you suggest. I had based it on fossils I found online, but sadly a lot of them are still outdated tail-dragging heffalumps. Well, that's my escuse anyway.
Excellent! I'm so glad to see it depicted with the tail held almost horizontally and its head upright, just like birds do. 
Two minor nitpicks regarding the anatomy if you don't mind . The thagomizer should point sidewards and the back wasn't as arched.
Ah so this is why you're so good with the dinos, you've had practise!