I highly recommend that you talk to a nutritionalist, or if you have a person at your gym that is a dietician or get referral to one who can set you on the right path. It is important to lose weight safely and effectively with healthy guidlines. Losing 'weight' can be easy, maintaining a healthy body composition, improved physical appearance and shape can be more of a challenge.
The 'weight' you lose should be the right 'substance', bodyfat, and not just excess water or in extreme cases lean body mass. Therefore, having someone that - can advise you and monitor your progress, check your health condition, is informed of your current weight and shape, knows the type of physical activities you engage in or like, understands what foods you consume and what foods you enjoy consuming..... can result in a successful weight loss program rather than entering into a dangerous yoyo dieting regime by just adding classes or eating different types of food.
When you increase your exercise program you need to ensure that your body is receiving enough of everything that it needs and your 'diet' is providing you with clean energy to burn. Possibly, by adding one more class a week could help you reach caloric deficit, but I dont know your situation or your health condition, so its a little difficult to answer your question.
BodyPump has absolutely helped me in my 'reshaping adventure' and I teach/participate in 3 BP classes a week, 2 to 3 BodyCombat, 2 Body Balance, yoga and spinning and I am very active out of the gym. This is possibly more than you want to do. What works for me, exercise or diet wise, does not necessarily work for another. Be realistic with your goals and with the time you have to exercise, make a total commitment to yourself and you'll reach your ideal shape/weight.
All the best.
List of things to do today.
breathe in
breathe out.