i'd say the WW15 is a great beginner's boat, but you need to stay away from demanding conditions until you have some experience. Conversely, a 45-footer might be ideal for Hell's Gate but it's a poor choice if you're just starting learning to sail.
I'd also strongly suggest some ASA or similar lessons, perhaps 101, then get a little experience sailing the WW15, then do 103 - for me this meant getting the best out of the 103.
I'd also strongly suggest some ASA or similar lessons, perhaps 101, then get a little experience sailing the WW15, then do 103 - for me this meant getting the best out of the 103.