This depends, to a degree, on what type of walking you intend to do in the future, after the WHW. If you intend to carry on walking fairly regularly I would invest in either Gortex or the cheaper Gortex clones. There are many lightweight waterproofs available today which serve their purpose quite well, but bear in mind that a summer weight one will not generally be suitable for winter conditions. However, a winter one will add considerably to your weight.

People will all have their preferences and will suggest, quite rightly, what works for them. I use a Phoenix Gortex coat and trousers for winter. Never let a drop of rain through yet but a Rohan lightweight set for summer ... much lighter and not as bulky. Also useful for towns as it doesn't look mountainous!

Really the best advice is to visit a specialist shop, tell them your requirements and try some on. Look at what others suggest on the internet to get some idea as to what will suit you.