I think I speak for us all A-Bomb when I say there's a large gap in the worldwide musical canon that a song about dental hygeine would fill nicely....
Or maybe a song about a clown with poor dental hygeine....
Or a song about a clown with poor dental hygeine looking for love...
There's your concept! Let me kick it off for you:
"I was just a foolish guy with a big red plastic nose
I wore a stripy jumpsuit and had clown boots on my toes
People saw my surface but never what was beneath
I'm sure they would have loved me if not for my stinking rotten teeth.
So I booked some time at the local dental place
Getting my choppers done would put the smile back on my face
The hygeinist was beautiful and it hardly hurt a bit
And while she bent down over me I reached out and squeezed her tit
CHORUS
I'm just a foolish clown who's lookin' for some lovin'
Don't want long term commitment, or a bun in the oven
But no-one will come near me I'm the halitosis king
If I can't get some lovin', then at least I can still sing..."
That's fantastic ! Can't wait to hear the harmonies.
Atom, there are lots of interesting concept albums from yesteryear that might be worth a listen, though I don't know your musical taste. "Tommy" {the Who}, "2112" {Rush}, "SF Sorrow" { the Pretty Things}, "A love supreme" {Chante Moore}, "Daughter of time" {Colosseum}, "Ogden's nut gone flake" {the Small Faces}, "The Tain" {Horslips}, "The rise and fall of Ziggy Stardust and the spiders from Mars" {David Bowie}, "The survival of St Joan" {Smokerise}. There's tons of them. Not to mention "rock operas" and rock musicals. What springs to mind with some of them is that a number of the songs were songs that the band/artist had lying around or were just written with no concept in mind but were sort of "worked in" to the album's concept and could stand on their own, independent of the concept album it's on. "Pinball wizard" from 'Tommy' is a good example. The album was moreorless finished when Pete Townshend wrote that, to appease a journalist that he played some songs to that found them boring and the storyline ridiculous. Half the songs on "Ogden" and "2112" aren't even part of the concept and were on the other side of the record. So not every song needs to "fit the concept".
Over the last four or so years, I've found myself writing a number of songs that, when I thought about it, had similar themes or were differing points of view of the same subject and as such, I'm kind of working on four concept albums. It'll be a few years before they're all completely finished, I tend to be very bitty in my recording in the sense that rarely will I start and finish a song in the same week. Try years ! But who cares ? I never take notes but I do jot down sentences and phrases here and there that I think might make good lyrics. Other times I'll just do a splurge and write a whole lot of crap and quite a few good lyrics have come that way. I don't put any rules on it. If it's an 8 line song, fine. If it's 10 verses, fine. At some point I force discipline and beat things into some semblence of shape.
One other thing I'd say is that you may be the only one that actually understands or even cares about the concept. So it should be accessible to any listeners, that is, listeners should love the songs, regardless of any conceptual considerations. A kid or an old woman should be able to dig the song before getting their head around "the concept"

. In a way, it's only in the lyrics that one detects that there's a concept. Who could guess "Ziggy Stardust" is about a gay alien rock star ? Or that Horslips' "Dancehall sweethearts" is about a blind Irish harpist ? Who could care less ?
"Not I", said the chicken.
I think it's fair to say most people hear a song before the lyrics or particular instruments (with the possible exception of the drums)
Easier said than done, but "just write" and manouver what you write into your theme.