As you can see the main colour palette is green and neutral. I tried to create a warm atmosphere by adding accents of colour (pillows, curtains, rug, paint) and textures (the wooden counter and wooden / stainless steel backsplash). I added a leather ottoman that also offers storage (that you can enhance with a 3 shelf wooden cart) and some chairs/sofa (of your choise from the ones I sent). The coffee tables offers flexibility thanks to the wheels, so the space can be transformed into a big playing space.
As for the mantle I suggeted a different design in which the fireplace is projected on a wooden wall with a wooden shelf on which you can place all sort of decorative objects. The Tv is placed above this shelf (I didn't suggest a model, I guess you will choose your favourite).
In the kitchen, I replaced the lights with others that resemble the ones that you mentioned. I made 2 proposals, so you can choose the one you like best, one more colourfull and one more neutral.
Hope you will like it!