I've got a Flextone II. My advice: don't use the wah pedal in the FX loop, it won't sound good, use it in front of your amp, in fact, the first thing your guitar hits. Then if you want to use the distortion pedal (on whatever setting you want on the Line6) to compensate, use it right after the wah, before the amp. But, before you bother with the distortion pedal, try fiddling with the settings on your amp. Maybe a little more or less drive, definitely more mids (if you've got the mids rolled of completely, there's half your problem for sure).