Plateau Problems

Have you recalculated your goal calories after the weight loss? Are you weighing your food? You could be eating more than you think. What about exercise calories? Are you eating some, if not, all of then back and how are you calculating them?

Try Paleo meals

50 carbs...30 proteine...20 fat

Protein Wise

Yeah; a lot of people make the same mistake with protein - where they have hardly any at breakfast, sometimes have hardly any at lunch (as most people love to do those healthy vegetable salads at lunch) and then have the big ole 200G-300G piece of beef at dinner; what essentially happens to that excess protein is that it gets broken down by gluconeogenesis into glucose rather than being synthesised into BCAA ( what effectively helps repair and restore your muscles after hypertrophy)

That big ole weightlifter myth of those massive protein shakes containing 60-100g of protein in them, they might as well be drinking a third of it and eating a chocolate bar, because it'd give them the same result. If you can spread it throughout the day ( 20 at breakfast, 10 in a snack between breakfast and lunch, 20 at lunch, 10 in a snack between lunch and dinner, then 30 at dinner ) then you'll get more value from the protein in terms of muscle development and restoration, but also protein is a proven thermogenic which should help top up your metabolism (especially if you're moving about during the day.

Water Wise

I'd say two litres is perfectly fine with the caveat that if you drink anything like coffee, tea or soda, drink an equal amount of water in addition to those two litres. The other caveat is that once you've been sweating for a while, replace those fluids ( ideally with a salt water mix to get the sodium back up if you're flushing too much of it out )

Exercise Wise

It may be time to look at heavier lifting or more intensity within your sets when doing strength work to build a bit more lean muscle mass, you won't bulk up (unless you're also eating a crap tonne of food to do so) and it will be a little different to what you have been doing.

Cardio wise; basically most research indicates you need at least twenty minutes of keeping your heart rate high and stressing your body in order to get the benefits from it; if you could increase to 25 minutes and do say 15 minutes of good quality cardio that gets your heart rate north of 135 and keeps it there, then add in ten minutes of interval/HIIT work that spikes you up towards the 145-150 range then brings you back to 135 then back up to 145-150 - that could have a pretty positive impact on your metabolism.

The reality is sitting on a treadmill for an hour and never going above say a 120-125 heart rate isn't actually that beneficial for you, unless you just want to get better at sitting on a treadmill for over an hour.

The other thing to look into is something along the lines of Crossfit, although personally too busy and travel too much for that, so I do a lot of Kettlebell work which combines aerobic and anaerobic exercises pretty well, is very functional and hits muscle groups that are usually pretty hard to find with most machine lifts.