To address the topic, I would say that vanishes and productions are amongst the more 'florishy' (aka Showing Off

) side of magic on the whole—but giving a vanish some 'raison d'etre' actually turns it into a trick!
To that end, it's always nice if a vanish 'trick' is impromptu, and gimmickless—as mentioned. However, some of the more impressive vanishes or productions are inherently gimmicked—TTs, Ravens, Thread, etc.
Nick mentions his 'what is in my pockets at this moment'. Well, I rarely leave the house on a night without a TT. My favourite EVER all time impromptu pub trick is to vanish a 'ready to stub' lit cigarette into someone's £75 Ted Baker T-Shirt. It's a jaw dropper, every time.
Coin vanishes are amongst the more visual for small objects, and there is probably more ways to vanish a coin without gimmicks than there are to skin a cat.
And the nice thing is, learning these vanishes can also help with vanishing other items too. It's all mainly, as Dale says, misdirection.
In fact, learning to vanish is possibly as much about psychology as it is sleights—focussing the spectators eye(s) into the area which you want takes a lot of skill... (i.e. having them believe a coin is in your LEFT hand when it's really in your RIGHT is a gem!)
Vanishing cards is also a dream, although this is DEFINATELY more of a flourish... or even a production of a Business Card from a Backpalm.
So... back to the topic, the starting point is to decide—are you 'flourishing' or are you wanting to perform tricks...
As mentioned, books like Bobo's will teach fundamentals in vanishes, such as French Drops, etc. But it's really vital that you see some vanishes being performed to realise how these individual moves are used to effect.
However... my FIRM advice, which is how it seems you are already proceeding, is to get a TT.
Here's some 'vanishes/productions' possible:
1. Vanish a silk hanky, completely
2. Vanish a LIT cigarette by stubbing it out into someone's clothing!
3. Vanish/produce salt or pepper from bare hands
4. Vanish practically ANY item of a feasible size
And of course, these utility vanishes can facilitate TRICKS too! Such as, bill switches, transpositions, colour changes etc.
Get a TT and a cheap TT pamphlet (i.e. 100 tricks with a TT) and see how you get on.
But remember, even with a TT, misdirection is going to be a huge part of the performance—the gimmick will NOT do all of the work for you.