Hello matroX,
For reasons I have not been able to discover, some machines do not utilize their full multithreading potential when exporting video. This appears to be quite rare, I've never actually witnessed a machine do this, but I have heard irritated reports from others on the forums. One of our testers has a 32 core AMD thread ripper and export used all 32 cores at 100%. The "ffmpeg" encoder option does indeed utilize x264 (unless you have a semi recent Nvidia card, then it will use ffmpeg's nvenc implementation). This is something I would love to fix if I can figure out how.
The encoder options are indeed for amateurs, which is by design. VirbEdit is not intended to be a pro or even semi pro software suite. Its target market is people who know almost nothing about video editing, and just want to quickly put together a video. It would be fairly straight forward to have a UI like Handbrake where we let you pick your rate control, specific bit rate or CRF, tune and presets etc. But there is really no desire to do so because that many options will overwhelm all but a small percentage of our users.
As for the quality of the output video, thats a subject on the forefront of everyone's mind, and we regularly make changes to try to improve things. There are a number of factors at play there. One of the most unfortunate is that when you add gauges to a video the over all encoding quality drops pretty significantly. We've found that Youtube suffers from the same problem. When you upload to Youtube, when it re encodes, the same video will end up looking much worse with gauges than the same video without them.
When you upload to Youtube, when it re encodes, the same video will end up looking much worse with gauges than the same video without them.