Just 'Acorns' would be a pretty awesome name. Except if you were going to go for the retarded acorns just acorns wouldn't really fit your kind of music.
There's an implication there that I find very interesting. But I digress - back to the topic.
Re: Massive Attack - whether "massive" is an adjective or a noun (gerundive?) is ambiguous. In "Blue Lines" it's definitely used as a noun, but in "Five Man Army" it feels more like an adjective.
I have to say that almost any band name of three or more words excluding "the", "and", "of" and proper names sucks almost by definition, but they're far from alone. A quick A-Z of crap names:
Acceleradeck - just nail a sign saying "WANKERS" to your heads, why don't you?
Bulletproof Electric Revue - and all other "randomly stab the dictionary" names.
The Cooper Temple Clause - see above, except worse because it was clearly planned
Delerium - misspelling words does not make you alternative and cool.
Evanescence - nor does making them up, you talentless emo fucks.
The Faint - either your band name is shit, guys, or you need to discover the Wonderful World of Nouns.
Gravity Kills - a cookie to the first person to guess this band's genre without knowing it in advance
Homliss Derelix - this act wrote a song called "Fuck You". I guess they thought the audience were making a request after the first number.
In The Nursery - the guy who named your band clearly never left.
Jah Wobble - WTF?
The Kingsbury Manx - we're back to "random shit" again.
Lacuna Coil - undoubtedly meant to be deep and meaningful; achieves 0 for 2.
Mr Mister - don't complain, though, the music is worse.
The Notwist - will be first against the wall when the revolution comes...
Oingo Boingo - ... but only if the list is sorted alphabetically.
The Pink Mountaintops - there is no excuse for this name other than a level of drug consumption sufficient to kill three bull elephants or Keith Richards.
Quarterflash - not too objectionable, but the worst Q name I could find. Feel free to add your own suggestions here.
Red Lorry Yellow Lorry - hint: attempting to make your fans look like dicks when they ask for your album is not the course of wisdom.
The Shamen - it's
shamans, you drug-addled raver fuckwits.
The Tiny Trendies - so twee it's physically painful.
UNKLE - if you're going to use an acronym, please have it be short for something. If you don't, I might start making answers up.
Vixtrola - imagine if Delerium and Evanescence bred. They'd call their kid "Vixtrola".
Wiskey Biscuit - too drunk to spell, it seems.
Xymox - I'm sure they named their band that so they could cheat at Scrabble.
The Young Gods - if ever a name screamed "pretentious poseurs", this is it.
Zodiac Youth - if the only way you think your album will be noticed is if it's the last one on the shelf, perhaps music is not the career for you.