So my band is going to switch to 8 strings soon (whenever they arrive

), and we've been pulling our hair out trying to figure out what to do with the bass. We'd tune to the same octave, but we're not going to be playing on the low strings all the time and playing on a higher Bb and Eb would probably sound wimpy. We don't want to tune an octave down because that's hard to handle with cheap bass rigs. So, my zany idea is to tune F Bb Eb Ab Db like we planned, but tune the F an octave up so it's like the 2nd fret on the Eb. So when we're gnarl-ing on the low Fs we're in unison, and when we go up to the higher strings we're an octave down like any normal metal band.
Basically I want other people's opinions on of this is a retarded idea or not. It's all hypothetical until we receive the 8s and try this out, but input would be appreciated