Meanings of the Marks

Hey, what's up, I wanna talk about cutie marks and what I think they mean, and what they do.

Okay, so, my main belief about cutie marks is that they represent three things:

1. A talent.
2. A passion.
3. A destiny.

And everything follows on from there.

The talent is a unique skill or ability (or small set of such) that each pony has. Let's look at the Mane 6 to clarify this point.

Twilight Sparkle: Powerful magic + rapid and potentially unlimited spell acquisition.
Applejack: Increased leg strength + ability to perform countryisms.
Rainbow Dash: Sonic Rainboom + general strong pegasus magic.
Rarity: Gem-finding spell + incredible telekinetic finesse + innate fashion sense.
Pinkie Pie: Summons party supplies + apparently her sense of humour is magical in nature.
Fluttershy: Speaks to animals + the Stare.

All pretty straight-forward.

The passion is a heightened interest in something:

Twilight Sparkle: Magic, and also friendship, (because friendship is magic).
Applejack: Family is important.
Rainbow Dash: Stunt flying and racing.
Rarity: Fashion and clothes.
Pinkie Pie: Making other ponies happy.
Fluttershy: Caring for animals.

Again, pretty straightforward.
A pony can have passions that aren't related to their talent! Or are only partly related. Pinkie and Applejack are both pretty good bakers, for instance, even if they don't have the marks for it. Pinkie makes supplies for her parties and cakes make ponies happy; Applejack's baking can eaten by her family, or be sold to provide money for her family.

Then there are potentially deeper meanings behind the marks, depending on your own interpretations, which reflect the pony's destiny. Let's look at Fluttershy, for example, because I've been thinking about her mark for a while.

Three butterflies. You know what butterflies represent? Change and growth. Personal transformation. That's been what has happened, right?

Fluttershy has grown a fair amount over the seasons, from barely even being able to look at a stranger without quailing in fear, to standing up for herself and her friends where needed. She has a propensity for going way overboard in her changes, sometimes, becoming somepony entirely different, like in the recent Fake It 'Til You Make It episode, transforming just a little too much.
She's had a physical transformation too, when she became Flutterbat, as a result of trying to force change on the vampire fruitbats. Her mark even changed there!
Fluttershy has also been able to facilitate change in others - Discord's redemption stands out here, but there is also her part in bearing one of the Elements... the Elements which perform changes on what they are used on...

And that's it! Any other interpretations?