It's a good start. I hope you won't be offended if I point out a few things you might work on.
First the yellow lugnuts shouldn't be yellow. They are normally just painted over when the road wheel is painted. If they are removed, some metal would show. Paint them green and then lightly go around the edges of each with a NO. 2 pencil. Also on the road wheels, the front one and the return rollers should also have the black rubber tires painted. And be careful not to let the paint go past the edge of the rim. On the drive sprocket use the pencil to go around the edges of the teeth to give a glint of bare metal where the paint rubs off.
On the exhaust, as you have it it looks ok, but to really bring it alive, drybrush some flat earth or armor sand paint on it to give it a more realistic sheen.
I don't want you to think you didn't do anything right, though. I think you did well on the paint and on the decals, so you have agood start. Perhaps the next thing you should get would be a set of artists pastel chalks, which are a variety of different colors, with which you can delve into deeper depths of weathering. Something you might use them for would be to blacken around the exhaust pipe and around the muzzle of the gun, where the gunpowder scorched it.
All in all a very good start on a promising career. My first one didn't, which oddly enough, was also an M-41, didn't look nearly as good. Modelling is something learned over many years of trial and error, so I hope you won't be discouraged by these few minor problems. Thanks for sharing your pics with us.
Rob