e# doesnt exist, i dont know what you mean by traditional music most american styles like jazz and blues dont say 'e#', same with 'b#'
if its in the key of F#, yes its a suspended chord with a seventh tacked on. not a bad sounding chord if you ask me. its a sus4 if the root is f#, (1 4 5 7), but its not a major nor a minor chord because it doesnt have a 3rd interval.
ive got some more larger chords for you guys to try if you like, the ones i like are: dominant 9th chords (1 3 5 b7 9), which can be played in A simply with 5-6-5-5-6 (fret numbers, from E to B. also you could include the A on the 5th fret high e string, but i dont). also, try my original chord with a b9 on it, in d# its very similar fingering to the dom9.try the m11 ( 1 b3 5 b7 9 11)
you can also try mixing up the intervals and leaving some out. alot of jazz guys omit the root in chords, but i prefer to omit the 5th because i dont like it. also, by omitting the root of a major 7th chord (used in jazz alot), it turns the chord into a minor triad that is 3 semitones higher (a c major 7th -> e minor triad). also, omitting the 5th allows for new voicings of higher chords like 11ths, 13ths that, because they have so many intervals, only have a few places they can be played.
mike uses alot of m3 diads, well so do most bands. also ive noticed alot of minor chords, suspended chords, and sometimes, like in godheads lament, he tends to pick a certain root (such as an A), whether on purpose or by accident, and then uses alot of the different types of chords with it, jumping from key to key. (i think i counted something like 6 or 7 different types of A chords in godheads lament - check out crep's threads, its very informative).
if you are going for a dissonant tone, try using chords with dissonant intervals like b2 (locrian scale is good for this), or with diminished fifth (b5 - try dim, dim7, half diminished 7 etc). minor chords, im often told, sound 'evil' and 'sad', so just add in b3 and b7 intervals. although personally each chord, whatever the connontations are, will sound evil, happy or cool depending on the individual. experiment with as many as possible, change them up a bit till you get ones you like, add passing tones, chromatics etc... and have fun!