Combine the courgette, fennel and dill in a bowl and toss with the lemon juice, olive oil and 1/4 tsp salt. Se aside and allow to marinate for at least 20 minutes or up to an hour. When you are ready to serve the salad, put the rocket in a large salad bowl. Scoop all of the zucchini and fennel onto the rocket, and pour most of the lemon juice dressing on top of that. Toss gently but thoroughly. taste and adjust with more of the dressing, olive oil, lemon juice or salt, if needed. If your lemons are particularly tart you may need to counter that by adding a little honey into the salad at this point. Serve topped with the pinenuts and feta cheese.