Looks a great starter army to me, it gives you the main requirements, you have infantry for bulk and to kill infantry, shadows for quick transport (be aware how vunerable they are though) and tank killing, and a tank to give your force some solidity.
You could drop the shadows for more inf, but I think that would be a mistake, as it would reduce your flexability, with that force you can also play a number of combinations that are less than 1000; which would be difficult to balance if you bought differently.