Awesome accomplishments to date! Do NOT get frustrated - the quest never seems to end. Like they say about "life", it's a journey, not a destination. - even if you do hit a goal -- what do you do? You have to maintain it. And we have all experienced plateaus, which is basically your body telling you it is now "used to" the diet & training you have been giving it. Time to tweak it again.
A couple of general guidelines to help you answer some of the above questions -
- Generally smaller meals, more often over the course of the day. In "dieting" terms, this ends up being something like 5-7 meals over the course of the day, every 2-3 hours. There are all sorts of "preferred" combinations of macronutrients you can try at each of these different meals-- protein + carb only, protein + fat only , etc. These you sort of have to research & try for yourself. (But don't let me get you buried in that part yet!)
- Training -- for fat loss, cardio is a great thing. But you don't need to become a cardio queen either. One approach is to throw in 1-2 cardio sessions per week where you do high intensity interval training (HIIT) -- which is basically sprinting for a short perid of time (e.g. 30 sec - 2 min) and then slowing down for a short recovery period and then repeating the sprint at intervals. This lets you vary the type of cardio you do so you dont' get bored doing an hour of slow cardio every day or anything like that. It also lets you "shock" your body with a little bit of a jolt so it doesnt' get used to just doing the long, low type of cardio. I think the boxing you are doing addresses a similar approach.
- Cardio on leg day? Personally I'm beat by the time I finish my leg workout & cardio just ain't worth it. Better to do it on any other day than leg day. I'll do maybe a 6 min warmup cardio to get things moving, but no more. Cardio the next day helps me to keep from getting too stiff from leg day anyway.
- Abs. Any reason you are doing abs 2x per week? I basically view abs as just another muscle group to train. I generally train each muscle group 1x/week. You might consider moving some of the work you do on one of the training days to go w/ the abs day(s). Just a thought.
Post your diet - times & meal plan for a typical day and I bet we can find a couple of easy places to tweak it to get things moving for you again!
Welcome aboard!