Hooverphonic rules, Self sucks, and Hum - Downward is heavenward is very possiblely the greatest thing ever recorded. I have said for years that if I could wish to have written one CD, that would be it. As for my suggestion:
Sensefield - Building
Apparently later on they got involved with some teenybopper crap show and totally changed styles, but the early stuff is intelligent punk at its best. It's worth tracking down. Even more obscure, and pretty much impossible to find outside of the Nashville area, and not easy there, is:
Crop Circle Hoax - Tour of the NATO Countries.
I have around 2000 CDs, and have listened to many thousands more, and this is honestly one of my three favorite albums. I can not say enough good things about this band. Similiar to the later Canadian band, The Pettit Project, but that's really the closest comparison I can think of. Geek rock with heart, I suppose.
Alright, one more, another Canadian band:
Moist - Silver
From start to finish, one of the best CDs ever. AFI with much better lyrics and slowed down, I suppose is close.
As for Hooverphonic, I prefer Blue Wonder Powder Milk, although The Magnificent Tree is really good too. Damn, this is just too hard, there's just too many great, obscure bands out there: Eve's Plum, Leaves' Eyes, Dambuilders, Salt... The list is endless really, so I'm shutting up now.