I think if your going black tie you should do it properly snd wear one - from a purely vain point of view of the wearer if fitted properly it always makes him look firmer/slimmer/fitter round the belly
The overriding principle of black tie is that any points of "utility" are covered up or smartened up. That is why good jackets have bevels not flaps on pockets, why buttons are covered in silk, why shirt buttons are replaced by smart studs and trouser seams are taped over with silk.
A part of that is not showing the waistline of the trousers (especially not with a belt!). So, your options are:
1) Keep your jacket closed at the waist at all times.
2) Wear a waistcoat. And, not age dependant - I wear one generally with a DJ and I'm young.
3) Wear a cummerbund.
Matching sets are naff IMHO. I reckon the best way of using them is to add some flair into a black tie party with a coloured cummerbund and normal black bow tie (self-tied). Less is more with colour. If at a sit-down dinner, keep it classic with black and white.
Bear in mind you're also sticking to "boring" colours so that the women stand out all the more. It's a type of uniform.
I agree - one coloured accessory only, hanky, cummerbund or buttonhole. Tartan silk bow tie at Christmas party maybe.
If you do not want to wear a waist covering of some kind invest in a double breasted dinner suit and keep it buttoned.
She sate upon her Dobie,
To watch the Evening Star,
And all the Punkahs as they passed,
Cried, 'My! how fair you are!'
Around her bower, with quivering leaves,
The tall Kamsamahs grew,
And Kitmutgars in wild festoons
Hung down from Tchokis blue.
Below her home the river rolled
With soft meloobious sound,
Where golden-finned Chuprassies swam,
In myriads circling round.
Above, on talles trees remote
Green Ayahs perched alone,
And all night long the Mussak moan'd
Its melancholy tone.
And where the purple Nullahs threw
Their branches far and wide,--
And silvery Goreewallahs flew
In silence, side by side,--
The little Bheesties' twittering cry
Rose on the fragrant air,
And oft the angry Jampan howled
Deep in his hateful lair.
She sate upon her Dobie,--
She heard the Nimmak hum,--
When all at once a cry arose,--
'The Cummerbund is come!'
In vain she fled: -- with open jaws
The angry monster followed,
And so, (before assistence came,)
That Lady Fair was swallowed.
They sought in vain for even a bone
Respectfully to bury,--
They said, -- 'Hers was a dreadful fate!'
(And Echo answered 'Very.')
They nailed her Dobie to the wall,
Where last her form was seen,
And underneath they wrote these words,
In yellow, blue, and green:--
Beware, ye Fair! Ye Fair, beware!
Nor sit out late at night,--
Lest horrid Cummerbunds should come,
And swallow you outright.