Please describe the problems with Tablet Mode from your point of view. As I don't have a device to try it myself I would really appreciate your opinion.
In general terms the over all feel is this is Win 7 on a touch device.
Taskbars, Scroll bars, Tab bars and other Desktop GUI elements do not need to be present at all times in Tablet mode. Tablets will ALWAYS have smaller screens all these Desktop elements always on and piled onto the screen take up WAY to much real estate and make it much more difficult to use and enjoy content.
Where is a Full screen web browser? Metro IE is gone and Spartan does not have a full screen touch mode. Again Web Browsing in win 10 has at least 20% of the screen being taken up by Taskbars, Address bars, Tab bars, Scroll bars
Swipe to get to the task view is a much less efficient way to scrolls through open apps as opposed to just swiping through all your open apps like in Win 8.
The Notification center needs power/restart, display brightness, time, volume control etc. They removed the charm bars and thought having an always on taskbar would replace it but then they don't realize how horrible that taskbar is for touch screens especially on smaller devices. Truly a domino effect of stupidity here. Move this stuff to the notification center and you don't need the always on Taskbar anymore.
The Expanded start menu is a very POOR replacement for the Metro Start screen. The all apps section to the left is a PITA using touch and is much less efficient than the ALL Apps screen in Win 8. Tiles can't be as well organized and up and down scrolling of tiles is not nearly as fluid as the left and right scrolling in Win 8. Also the Start menu does not work nearly as well with active Live tiles. We should be given a toggle in the Tablet mode settings to use the old Metro Start screen instead.
Win 10 has a "Desktop" AND "Tablet" mode their is simply no reason why each mode cannot be setup to work as efficiently as possible for the type of device you are on.
Desktop mode should closely resemble what we have now in Win 10 and toggling to Tablet mode should auto arranged things to work more like Win 8. It is pretty simple how they need to fix this but they do not have enough time.
Like I said to sum it all up MS threw away everything that worked well on Tablets in Win 8 and just decided to tweak Win 7 for touch devices.