Crest Elements / Crests in S3 and S4

My theory is that each crest has its own element, and that we can fit crests to the Tamers and Frontier Kids using these elements. Remember, these are just my theories! Let me know your ideas. (I'm not going to go through Miracles and Fate, as far as I'm concerned they're one-offs.)

Courage

Element: Fire. Tai's and Davis' Courage-digivolved Digimon are both full of fiery spirit, especially Flamedramon.

Tamer: Takato, because Guilmon seems to be a fire element, and because all the goggle boys would have Courage.
Frontier Kid: Takuya, because his Spirit is Fire, and he's a goggle boy.

Friendship

Element: Electricity. Raidramon and the Gabumon sequence both have electrifying attacks!

Tamer: Henry? I know Terriermon isn't exactly electrical, but he's definitely a really good friend.
Frontier Kid: J.P., because he has the Spirit of Thunder. Or Kouji, because he is like the equivalent of Matt.

Love

Element: Wind. Yolei and Sora both have flying Digimon.

Tamer: Rika, because she's a girl, and Renamon can teleport, so she moves as fast as the wind. Also, she has a heart symbol on her T-shirt.
Frontier Kid: Zoe, because she has the Spirit of Wind, and she's a girl.

Sincerity

Element: Wood or Earth. I dunno, Palmon's sequence just seems to be wooden, and Shurimon...is Shurimon. It could be Earth, but this one needs some thinking about.

Tamer: This one's a hard one. Perhaps Rika, again.
Frontier Kid: Zoe again, because she's a girl and she tries hard to be sincere.

Knowledge

Element: Steel. Tentomon's sequence and Digmon are both pretty steely.

Tamer: Kazu, because he's got Gardromon.
Frontier Kid: Maybe Tommy, because he loves to learn. Just like Izzy.

Reliability

Element: Water. All the Reliability-digivolved Digimon love the sea.

Tamer: Kenta, because MarineAngemon is a sea animal (and it's also the Mega form of Joe's Digimon, Gomamon)
Frontier Kid: No one, really. Maybe Tommy, ice is kind of like water.

Hope

Element: Air. Angemon and Pegasusmon both love flying.

Tamer: Maybe Suzie, because she's always hoping?
Frontier Kid: Tommy, because he's a little kid who is full of hope like T.K..

Light

Element: Light. You can't really describe Angewomon and Nefertimon as anything else - unless you call them angels.

Tamer: Ryo, because he is the guide - the beacon, if you like. Besides, I'd classified everyone else, and he's definitely not Earth.
Frontier Kid: Kouji, who has the Spirit of Light.

Kindness

Element: Darkness. I'm not sure, but I think Kindness would be darkness because of Ken's personality.

Tamer: Jeri, because she gets depressed and stuff after Leomon is deleted.
Frontier Kid: Kouichi, because he has the Spirit of Darkness. (Not to mention that he and Ken are both really cute! But Kouichi's cuter. XD)