Thank you everyone. Seems like I've been wrong, and probably should re consider about my gear upgrade. The thing is, everybody has a different taste in photography. For me, the images on Elliott J. Coleman Photography – Capturing the natural beauty of Wales pixel by pixel look perfect and this is what I'm looking for. It may not have a perceptive, but I find them beautiful. Now that I already have Nikon D3200 and 18-55mm kit lens, which other lens would be best for these kind of images? I'm not looking at architectural or building pictures, but rather mountains and seascapes.
Also, I'll always keep 18-55 with me if I'm taking long exposure shots of waterfall, or mountains but I need to have a lens that can allow pictures of landscapes and mountains from a wide angle.