I was eagerly looking forward to deepin 15, as I loved 14.3 but it had a few quirks/bugs, namely screen flicker when the file manager was open, slow speed when copying to usb devices, intermittant wifi issues and some apps not fitting the screen properly. But despite these flaws I stuck with it as I love the interface and simplicity of deepin and for the most part it has served me well.

Then along comes deepin 15. What I like is that you have stuck to pretty much the same layout and the deepin store looks even better than the old one. Sadly I have had a few problems with this release:

1. The deepin store is slow to load.
2. There are nowhere near as many apps available in the store as in 14.3 and the search function seems to bring up hardly anything. So then I've had to use the terminal to get apps that previously were in the software centre. While not a huge issue it does seem like a step back to me.
3. The dde seems laggier to me than in 14.3
4. The system update doesn't work very well. It is slow and frequently hangs. Have tried changing the mirror, but it is hit and miss when this actually works. It worked better for me before when it was part of the deepin store.

I am having intel gpu related problems specific to my laptop which weren't present in 14.3 (other than screen tearing) and acpi issues. The driver manager is unable to offer a solution. I don't know whether this is due to using a newer kernel or the switch to a debian base, but I think you should've stuck with ubuntu as it seems to be more compatible with more hardware, after all you aim deepin at new users and we want something that works well out of the box.

While I appreciate you are patching/improving deepin, for me at the moment it just isn't as good as the previous version. I have switched to ubuntu 14.04 Lts for now, and have to say it works much much better on my hardware. I will try deepin again in the future as I do like what you're trying to do, it's just unfortunate it isn't working as well as I'd hoped.