Here is a suggestion!
If one of you knows how to make a Custom ROM then please see this post.
For all the users who think Tab 3.7.0 (In this case SM-T210) is dead well I still have one more solution that could save it.
As I made it obvious, I am here for the same reason that you are here, which is to find a fast custom ROM for your Tab 3.7.0 which I even own.
I've searched every website to try and find a good Custom ROM for the SM-T210 but it didn't quite work. I ended up finding an abandoned Cyanogenmod instead
I am currently running this ROM because nothing is getting me to go back to the old regular Stock ROM.
My Opinion on the Cyanogenmod that I am Running isn't bad. I actually found it very useful apart from having the audio problem (Which they confirmed they fixed but didn't).
I have no idea why they left this ROM. They could have continued working on it and making a successful ROM for this Tablet but they decided to stop
Anyone who knows how to make some sort of Cyanogenmod get the drivers of the Cyanognemod I mentioned and try to fix them and make a better ROM for all of us!
Thanks for listening and I would like to wish the developers of this ROM Good Luck.