This is not an full answer to your question. But I am very interested in how did you build your own 2-qubit device, as I am thinking about such a project for some months now. Would you mind to get in touch with me and exchange our thoughts on this?
I would really love to get into discussions with you, maybe you could support me to build my own device?
Regarding your questions, there are a lot of tasks in the MS Quantum Kata series, that only work with one or two qubits, maybe you'll like some of them, e.g.
https://github.com/microsoft/QuantumKatas/tree/master/CHSHGame
https://github.com/microsoft/QuantumKatas/tree/master/Superposition - Hardy-State