The short version
Huai Khwang is a useful middle ground between central Bangkok and the northern suburbs, with a busy MRT corridor and a large residential hinterland. The station area is energetic late into the evening, especially around Ratchadaphisek. Farther into the lanes, high rise towers give way to smaller homes, workshops and less polished streets.
Choosing a pocket
Near Huai Khwang MRT, the advantage is obvious: food, shops and taxis are close, and the Blue Line makes central journeys straightforward. Around Pracha Uthit and the lanes towards Wang Thonglang, life is more local and usually more car dependent. The area has a strong Thai Chinese and international commercial presence, but it is not a single expatriate bubble.
Noise and movement
Ratchadaphisek is a serious traffic road. A flat advertised as “near the MRT” may still face road noise, and walking crossings are not always graceful. Choose a side street only after checking the route in person. The station corridor is convenient; it is not tranquil.
My verdict
Huai Khwang is a good shortlist candidate for a professional who wants central access, late meals and a large choice of apartments without paying for a riverside address. It is less suitable for anyone seeking low traffic streets or a village atmosphere. I would live near the station, but not directly over the busiest commercial frontage.