We’re in the process of improving on some of the issues listed in this thread (a combination of fixes, and some new Live TV & DVR features). Most notably Watch from Start not being shown, and improving on tuning times, as well as the ability to see the guide without stopping playback. You can read a bit more about some of the work we’re doing here: Live TV & DVR: Fixes and Improvements
This is by no means an exhaustive list, but some of the things we’re close to releasing. 