Thanks for your time, talking with a KDE developer is important to me. The reason for choosing Vulkan was about explicit control over synchronization, resource management and frame scheduling, without having to maintain also OpenGL; even though I don't exclude a software rendering fallback for VMs or something. It wasn't a first-minute choice, I realised it when I wanted to improve performance compared to other DE. Currently I'm developing a benchmark suite, this is not complete yet but I've already found out Vela around 40% lower input-to-display latency in one of my tests (compared to Plasma), apparently thanks to late latching.