Oi Edmund you git! Wher iz da Goffs?
That said I would agree with Da Freebooterz though, you can do what ever you like with them.
CGoM, there are a few things that will help make you stuff look a little snazzer.
The classic 'Drill the Barrels out'
This makes a big difference to the look of the all the weapons.(It will also get mentioned any time you post some pictures.
If you don't have a pin vice drill, paint black to hint at a muzzle.
Using washes makes this even more important than normal as the ink will pick out any you don't scrape off with a knife.
The last thing is give the base edges another coat of paint, the black is showing through a bit.
You have a nice army, coming together in this thread and I love the 'rank' based warpaint idea.
The rhino could do with being more orky, but I understand the urge to try and use it for both your SMs and Orks and save some cash.
Magnetized orky Armour plates would be the solution for you but as you have already painted it up I will throw out an idea that may be of use.
You can just paint up a few random ork fixins plates made from plastic sheet (Try margarine or Ice Cream tub lids for a cheap source) and Blu-Tack them on when you are using it for the Orks.