I just installed the PTS yesterday, started new BH and played through the starting planet.
Here are a few things I've noted so far...
1. I didn't experience many of the overlaying zoom/overlay buttons that others have stated, but then I am using a 4K monitor at full resolution. May have something to do with it. I will say though, I great that you added the ability to rotate the char using the mouse, but not that you took away the ability to move it up/down/left/right. Only other option I have is zoom, but can only zoom in to the mid-torso; which is fine if you have a belly button fetish. The previous method may have been a little clunky, but it worked.
2. I have enabled main quickbar and quickbars 2, 5 and 6. I have assigned key bindings to all. But, it looks like any key bindings assigned to quickbar 5 do not work. Moved the same key binding to quickbar 6 or 3 and it works fine. Not too big an issue, just don't use #5.
3. Now that abilities are auto-trained, and don't appear on the trainer's menu, the option to view all abilities, even though not available yet, has also been removed. Now we can't see at what level an ability can be acquired. [Edit] When selecting to show All, it now displays abilities not yet available. Not sure if this is because I'm now off the starting planet or fixes made since prior login on PTS.
4. Please bring back the sell all junk button when interacting with a vendor. It was very handy to first sell all junk, then weed through the other sellable items. [Edit] Button is now back, not sure why.
5. Two things with the Inventory panel.
a. The key binding only half works. It is supposed to be a toggle on/off. The key will open the panel, but will not close it. This will be a major nuisance if not corrected.
b. What is up with the Currency tab? There is a big pink button on the lower center. Does this mean it is a Work In Progress? Or is WIP a new type of currency?
6. Is there a way to turn down the mouse sensitivity in the Preferences? If so, I can't find one. When I play the current production game, my mouse-look movement seems fine, but it seems a little more sensitive in the PTS.
7. This is not a new bug, but something that I've experienced on the PTS as well as in production (for a very long time) and is very annoying. When I'm moving around, forward for example, and I use the mouse right-click to change direction, often the camera will suddenly flip to looking straight up and that char will change to some arbitrary direction. When it happens, have to immediately stop moving and reposition the camera forward before continuing. It's very disorienting. Hopefully, not near a cliff or edge to fall off. Usually, wind up running into a tree or rock that I was trying to avoid in the first place.
8. My opinion is still undecided as to how I feel about the new character panel, combining the inventory. For example, I have the regular inventory panel open and have my mouse positioned over a particular item and want to manually equip. Then open the character and the separate inventory panel closes and the character panel opens with the attached inventory. Now have to relocate the item in the other inventory.
9. On the character panel, Outfitter tab, it's nice that you have added the main/offhand weapons. But, they do not work. When trying to drop a weapon to it, says not the correct item type.
10. I do like that the class-specific ability (e.g., Hunter's Boon) is now a passive instead of active. No longer have to worry about looking down and see the buff(s) have expired.
11. I see the same bug present since roughly the beginning of SWTOR. Yes, I've played since the initial beta. The galaxy map icon on the top menu begins flashing half way through the starting planet noting the availability, but you can't open the galaxy map until you complete the first two planets and acquire a ship.
12. Another old bug...When I start a new character, typically get 45+ mail items (past year sub rewards, etc). As I'm going through them, the list continuously reorders every time one is deleted. The default order is by date/time received. Since they all arrived at the exact same time, the order within date/time appears to be random. Which is very annoying weeding through all 48. The previous/next buttons on the open mail detail panel is very confusing since the next mail item may be one you have already read.
13. When looking at the map on the fleet station, the radio selectors for the legend (e.g., Vendor, Taxi, etc) used to be accumulative (could be multiple). Now it seems we can only pick one at a time. Is this supposed to be this way now? Also, not if this was a fix to a previously unfixed bug; occasionally when opening the fleet map and having say 8 of the 10 selected, the majority of the legend icons would disappear from the map. Only way to get them back is to re-log or possibly leave station for a while and return and maybe they might come back. Note: when this occurs, turning the legend option off then back on does nothing.
That's all I have for now. Sorry they are not organized better, but was writing them down when found.