Nothing magical about this oaf except his amazing ability to troll anything and everything within a 10 block radius. He's an expert at knife combat, and more-so to a concentrated degree at throwing knives; he'd been to an academy and has worked in the war as a [foot]soldier, so battle, while typically scarce in his present work, isn't new to him. One very important strength--probably the one most would associate with him, considering it cost him his life--is an uncanny ability to investigate and get answers people need. His intuition is solid and his skill at sitting at a desk into the wee hours of the night is unparalleled.
Oh, and one cannot forget to mention, he's pretty good at hiding when danger's around. Because honestly, when there's a Hawkeye and a Mustang around, why need him? He'll just be behind that tree over there until the dust settles, thanks.
How would they use their abilities?: It's a general rule of thumb that when you're good and throwing knives you can probably 'cut a fool'. While much weaker than an alchemist and not as handy as Hawkeye or a more active soldier, he is capable of keeping himself alive (unless you turn into his wife, to which he can say 'fool me twice, shame on me'). He is capable of using firearms--it's one of those mandatory things, after all, and his aim isn't half-bad. Just don't choose him over Riza to do any real shooting.
Hughes will, besides defending his life or others' if need be, keep vigilant to his typical paperwork and/or missions, and he'll definitely be around for any Intel that may blow over in his general vicinity.
Appearance: Hughes is a Caucasian man, fairly in shape, and definitely a handsome devil if he the mun may say so. He's typically seen in the Amestris military garb, complete with rectangular glasses--after all, a man lacking 20/20 vision can't read his paperwork without 'em! His eyes are golden and his hair is jet black (though it is sometimes a dark green in hue, a sort of stylistic black in the animation). If you saw this man in silhouette form, one very distinguishing feature would be a lone hair antenna, sprouting from the front of his hairline. If you see this outline, you might want to find a good hiding place until he passes.
(Because Hughes suffers from Only-a-few-chapters Syndrome, The first paragraph is entirely fanon and is simply there to help reveal a little of why Hughes started shooting for military life.)
Hughes was born in Amestris, to a doting mother and a hardworking father. Growing up he was showered affection as an only child, though his father--a man who worked in the military--taught him sternly, and with time made the young boy decide the career choice he wanted: to be someone that could help the country and the people within it. By the time Hughes was on his way to the military academy, his father had already retired and passed away, but he was determined to continue his father's ideology and do right by him.