Coats are so subjective to me. It really starts to get into personal opinion because there are so many right answers. Sure there are some daffy ones out there, but by and large, it seems that any conservative, traditional coat is a safe bet. If it's cropped, I may be concerned for it's style longevity, but other than that, it's probably fine.
That being said, I would personally not buy a trench I couldn't fit over a suit jacket. If I'm going for a casual, thin, short jacket, it wouldn't be a trench style. Too many buttons, the doubler breast, and the belt is a pain. I'd want something more convenient. And if you're actually attempting to use it for rain, you're only covering half your body.
If we're talking about the one nicholascrawford thinks it is, I can give my opinions, but they're only that - opinions. First, I REALLY appreciate that it has no belt. It's one less thing to fasten up, reduces clutter, and makes the whole thing look sleeker. On the flip side (literally), I'm not a fan of the pseduo belt in the back. It's not inherently feminine, but I've seen it on so many women's coats lately that it's the first thing I think of when I see it.