Hey S.,
I can tell you upfront that weaning will not help you loose weight faster. IF you do wean, like you mentioned, you will have to adjust your calories as your appetite might remain a little longer and if you stay at the same caloric intake as when nursing you will actually gain weight.
If your goal is to lose weight, it is not contingent upon weaning. Weight is all about, age, metabolism, stress, food/caloric intake, exercise/energy expended and SLEEP.
It is expected that weight loss following a second pregnancy will be less and take longer, but that does not mean you can not get back to your pre pregnancy weight. It can be done in a healthy way.
As with age, we all have to be careful how fast we add that pound or two. This just means being cognizant of how much we consume for how much energy our bodies use to stay at our "maintenance" weight. It realies is about the number of calories, but still try to make healthy choices. Especially while you are making milk for your little one.
Stress is important in that if you are overly stressed your body produces more cortisol which is essentially a steroid hormone and can keep the weight on.
SLEEP.. .this is the most important thing anyone needs who is working on weight loss. I can attest to this as my first child didn't sleep do to severe acid reflux and neither did I for almost 2 years. I maintained my same diet and activity level and my weight was finally right when I became pregnant again. And now with another newborn, I lost all but 9lbs by 2 weeks(And I had gained more with #2.) Crazy that the only difference in the both babies is that I slept for the second.
I would tell you to review your sleep, calories, stress, activity level and adjust them to fit your body's needs. If you want to wean then do so, but I do not think it is going to help you loose or gain weight. However it is allowing your palette to enjoy more foods as your body is burning more calories to make milk.
I hope this is helpful. You sound like a wonderful mom. And like you, I just love the bonding from breastfeeding.
-MB