Been there to sail, but had just learnt so was on learner board at the end of feb, if I remember right.
I would imagine it gets damn windy in summer, its a nice bay, a bit like sailing around lancelin I would guess without the reefs and your on starboard tack.
There is a decent wave spot not to far from there 1 hour away I think, and I think there is some wave sailing to be had but nothing huge. I rented from the mistral centre, gear was fine, up to date mistral and north, not sure what they would have now.
On the shopping front, I really like the town, as it a bit out of the way for the European tourists, so its pretty interesting with a nice souk, so good shopping but not necessarily what you wife might have in mind

I have been to lanzorote which gets the same wind, which is a different experience, as there will be many more european tourists (along with the irish pubs etc), with more choices to rent gear, and locations to sail plus its easy to rent a car there. (you might not be able to take rental gear away from the centres though)
I took the bus to Essaouira from marakesh, and did it cheap, its a fun experience, I don't think you find a irish pub in Essaouira.