Android and metro versions of the control app, and CI would be nice. AppleWatch control surface would be nice. But I am not sure why focus on features with such a low utilization, seems like gimmicks.
Rock solid playback of at least 2 4k clips in cross fade with 3 effects applied in 32-bit color would be more useful. But maybe this all exists but we do not know what the hardware config is to achieve this.
h.265 support, multi-gpu support of opencl, image recognition of TC slates, audio recognition of slate clap, auto multicam sync and color balance, sony f-series native raw support, prores export via opensource, fluid workflow in 32bit color, handle media and colors like nuke does, DCP creation. Features like those would propel vegas further than ipad touch controls and Ci.