I have no experience with TCL, but my opinion is to avoid the built-in Roku. Just get the TV you want and buy a separate Roku device. In my limited experience, the dedicated devices are faster than the built-in software, and as Roku comes out with better and faster devices, it's easy to upgrade. I have a Roku Ultra for the living room and a couple of Expresses in other rooms. The Express would be fine for your daughter, and they're currently $24 for HD or $30 for 4K on Amazon.