I suggest you just leave it alone, a lot of people brick when they try to remove stuff without knowing what they're doing.
It shouldn't cause any conflicts with BootMii when it is released.
If you want your system menu to look normal again, just install the original .app file with SoftMii tweaks (I hope you backed it up)
But if you really want to get rid of SoftMii (Preloader, cioscorp, cios rev 11, HBC), then you can do this:
WARNING! DO NOT DOWNGRADE IF YOU HAVE A LU64 WII
-Run
IOS Downgrader (That should get rid of most of cioscorp)
-Run
Custom IOS Downgrader and choose System Menu 3.2 (Make sure you choose the right region. That will get rid of preloader)
-Use
AnyTitle Deleter and delete IOS249 and IOS250 (That is cIOS rev 11)
-Use
NANDClean to remove preloader settings, hacks, installed dol, and system menu app (That will get rid of the rest of preloader)
-Delete Homebrew Channel from Data Management if you want to (This will be needed to install BootMii, so you probably don't want to)
Now you should have a virgin Wii with System menu 3.2.
If you want, you can update to 4.0 through Nintendo.
But if you do, make sure you have Homebrew Channel installed BEFORE updating (You won't be able to install it after)
