check if the screen is connected propperly (even experts sometime make mistakes) then try to shine a light on it and try to see if its the backlight thats broken... also, if you paid via paypall you can still get your money back and ebay also has something like that, try to contact them
you need an OEM screen (i have previously bought non oem screens.. and well.. dont.. just dont..) you can buy a screen from ebay .. also i reccomend buying the screen with frame.. its a real pain to take of the screen (motorola uses overly strong adhesive) http://www.ebay.com/itm/OEM-For-Motorola-Moto-G-XT1032-1033-LCD-Touch-Screen-Digitizer-Frame-Assembly-/201456412153?hash=item2ee7bce5f9:g:RAUA... should work for you.. if you need any help, ask me.. ive got some experience after breaking multiple screens this month
id reccomend taking the thing appart, and try to clean the lens, it could also be (if your device has optical focus (identifyable by faint clicking noises when it focusus) and water coming in there, and leaving ressidue in the mechanism, this can be fixed by washing yoour immage sensor in 96% alcohol in a super clean container, and let it dry out (make shure to not add any impuritys to the alcohol like water or using a container with impuritys in it
you probably have a defective battery, or the battery charging circuit has been damaged, the flickering of the screen is because the screen doesnt have enough power to stay on, so it turns on turns of turns on turns of etc. really fast wich creates the flickering, for the slow performance/unstable performance, the processor would be undervolted, would be an explanation, try to hook the tablet up to the charger, does it make a difference?
i would recommend to try to delete some apps, if you use whatsapp, then also go into a file explorer and delete/ move photos to your sd, and in the settings you can go to storage, and delete cache, for a temporary speed boost, and also look where the most of your storage is used!
so i ended up just trying it out, i stripped some pins from an even older broken gpu (it was pretty much worthless..) and soldered it onto my videocard/gpu, then i found a xfx vga 12 pin adapter and put it on, but unfortunatly, it didnt work.. so because i didnt have a adapter or converter, i looked at my pc one more time, and looked at the vga connector on my motherboard, plugged it in, but it didnt work, so i researched it a bit and found out, that you can go into the bios, and go to graphics settings, and put the order in wich the pc finds the videocard to first find the gpi (integrated gpu) so it will find the vga on the motherboard, and then the videocard, i plugged it in, and it worked!! succes!, i want to thank you guys for the help, and i hope somone else also finds this to be usefull! https://www.youtube.com/watch?v=N8nMShuS...