While it's probably unnecessary given the length of this thread, hopefully some more input won't hurt.
Above anything else, this new upload queue system seems incredibly counter-intuitive. I understand that many problems still need ironing out, so more minor details will just take getting used to, but even conceptually I don't understand what this is supposed to accomplish.
In the first place opening the pending status page in a new tab just leaves the original upload tab as a useless extra, and either way, having that instead of an immediate direction to the completed post doesn't present anything that we would be unable to see after the fact.
I can't speak for anyone else, but personally I like to at at least quickly review a post after uploading, to see if I made any typos or blanked on any important tags, which becomes a very tedious process with the use of this system. Not to mention attempting to connect parent and child posts in quick succession.
A lot of this might not even be as bad if the queue moved at a decent speed, but from what I can tell any somewhat large upload or busy period has the potential to completely clog everything up. If that were less of a problem, the general concept could be just a minor annoyance at worst.
I'm trying not to come off as against the site upgrade in general, aspects such as the tag separation in posts feel like a natural progression, but uploading has almost become a chore these past few days. I enjoy trying to contribute to the site and showing support for series and artists I like, but it just isn't always feasible to wait an hour or ten in order make sure I typed something correctly.