Felixstowe is a bit of a mixed bag, MM. Felixstowe Docks almost forms a separate town to the main conurbation and, by its very nature, is a very industrial area. However right alongside there is a Landguard Nature Reserve, which is lovely.
The main seafront is very run down at the southern end (with tatty amusement arcades, etc) but the northern end has some lovely gardens is very pleasant.
The town itself isn't that spectacular but it's got two of the best second hand bookshops in the area (although one is currently downsizing and moving into the basement of its existing premises), as well as several nice places to eat.