If you like your existing living room switches, if they’re the zwave ones they should work fine with SmartThings, no need to change.
If you want color for your child’s room, hue bulbs combined with the mood cube controller project is very popular. You could also just do this with some table lamps in a section of the living room.
We should note that it is a bad idea to use a dimmer (smart or dumb) that controls the actual current to a dimmable smart bulb. You will likely burnt out either the switch or the bulb as they will confuse each other.
You can use a smart dimmer with dumb bulbs. Or you can use one of the various methods that uses a dimmer switch which is controlling the same circuit as the dimmable smart bulbs.
