Aura H2O Slow Kobo -- Should I reset it?

Hi there,

My Kobo is great. I love it but recently there have been some problems.

I'm a person who likes to have a lot of books on their device, all of my books are on an SD card and not on the device itself. I think I have around 10,000--mostly fanfictions with some novels thrown in there too. Everything is organized in Calibre in shelves and such, so I don't think erasing everything and starting over will be too annoying.

My issues:

• Restarts-For the last few days when I open a new epub book (made in calinbre) my kobo just shuts off and turns back on. One book opened after the restart, but another just causes it to restart over and over again. Both epubs worked fine in Calibre.
• There are a few other restart bugs like if the screen locks in a book I need to force a restart because it won't unlock.
• Slow restart - when it does restart, the restart is very slow. It takes about 15 minutes to be usable. It loads the home screen, the battery indicator goes to about half (regardless of how charged it is. When it is done restarting the battery indicator becomes accurate again.) also covers don't load. I can not do anything while this happens but wait.
• slow in general -- this one I think is just because of book quanity, and when I am reading page turns are fast but the gui is slow when I navigate around.

So I am thinking a of wiping it and starting again. Will this help me? Do you have any other suggestions on how to make things go faster and more stable?

Thanks!