Personally, I think a 18-135mm is perfect. The added zoom is a game changer. I struggled with just a 18-55mm for years, now I can't even imagine shooting with one. Something like a 50-250mm or a 75-300mm are nice for very specific shots that you might want to get, but an 18-135mm is ideal for everyday use. Here is a video I shot with the 18-135mm the very first day I got it. Hopefully It'll give you an idea of how it performs.