If you can still access HomeBrew Channel, then you don't need to letterbomb it again.
Look through the Softmod Any Wii guide that I have linked in my signature and go through it completely.
When you are given the choice of exploit to use, choose the one "for systems already with HBC". Everything you need will be run through HBC and you won't have to letterbomb it again.
Go through all of the optional stuff in chapter 2. ModPack, IOS Update, Menu 4.1, Priiloader, Wii Shop v21.
Installing IOS Update and a fresh Menu 4.1 should get you back to where you want to be.
Don't uninstall, delete, or format anything first, just remod on top of what you have.
Then stay away from themes.