Sounds like my tabby
Your description of your kitty sounds a lot like mine. I got mine when she was 7 weeks old from a shelter near the Mexican border in U.S. She's always been on the wild side (spitting, acting a little agressive, stalking..etc.) The vet said that she might have wild blood in her, it wasn't very uncommon. She is now 3 years old. She is a lot friendlier but she still has a feisty nature, which I love. She looks like one of the ancient sacred cats. She has both spots and stripes. She is about 15 lbs, very muscular and larger than average tabbies. Her paws are black and her ears are kind of reddish. She is incredibly intelligent too. She plays fetch and knows many commands.
I am thinking that she might be an Ocicat because of large ears and pointy face. Your kitty does not look like a typical Oci because he has a roundish face and round eyes and smaller ears. American short-hair is definitely a possibility, they are called Tigers in the U.S If he has wild blood, it is probably a mountain cat which are fluffier and have round faces. Mine is probably a desert one.
I hope this helps..
By the way, how is your cat's temperment?