The easiest fix is setting your core usage for your BitRaider and SWTOR Launcher to 2 cores. This is the reason why newer PCs have this issue but older PCs are just fine. Let me know if it helps!
Adric_The_Red is correct. If you delete your character and your items/mounts are in the collections it should be fine. If they are in the inventory or cargo hold, etc they will be deleted along with the character