Coat of Arms - Can work, but you have the Champion and the Imperious Perfect anyway. I don't know if you should use it.
It's a finisher that I play in more casual games. In tournaments, I use Overrun now.
Allosaurus Rider - Seriously, what? No land fetchers and cheap cards mean it might not work well. I say you should remove it.
It's a "free" dude--free as in it doesn't tie up your mana. If I have irrelevant cards in my hand, such as mid-game Llanowar Elves, I can pitch it to him. Plus, I have enough mana acceleration that I can hardcast him if need be.
Wellwisher - I don't like it, but you are free to use it. It doesn't help much in the rest of the strategy, though.
Wellwisher is only for multiplayer games, where constantly gaining life keeps you in the game. In duels, life gain slows elf decks down. Plus, this card is no longer Standard.
Llanowar Wastes - Lol, Ravnica duals are better. Use Overgrown Tomb. Better than painlands anyway.
Overgrown Tomb isn't in Standard anymore. I use Tomb only in the casual version.
Spawning Pool - And this is in the deck because? I see no connection, and I think this cycle fails except for the green one. Not really worth.
Again, this is for the multiplayer variant. Your big fatty is no longer a threat to me until it gets trample. Then I'm screwed anyway.
Treetop Village - It's an Ape. O_O You can use it if it works well for you, but it's not something that'd be definitely put in an Elf deck.
3/3s that survive Wrath of God are great. Especially since they only cost 1G to use.
Harmonize - What?
Do you not see how much mana acceleration this deck has? Harmonize is fantastic against control decks. If they counter it, that's a counterspell out of their hand. If they don't counter it, it puts more threats in your hand. Against aggro decks, it puts cards in my hand, which means I have more men to drop and more answers for my opponent's creatures. In aggro mirrors, the creatures and burn spells tend to cancel each other out, meaning games tend to become a card advantage race. Drawing three extra cards can lead you to a tremendous advantage.
Eyeblight's Ending - There are better ways to destroy. However, this is an Elf card. The thing is that I think no card in your decks can combine with it in any way.
Eyeblight's Ending is an Elf card, meaning you can search for it with Elvish Harbinger. Also, there isn't any cheap instant speed death in Standard other than this and Nameless Inversion.
Okay, Elf means quick Aggro things. Go for token-makers like the Imperious so you can exploit the Heedless One, the Archers, the Champion and the Imperious (and the Wellwisher if you're keeping it). Otherwise, you have limited ways of winning. More spells would work, too. Try the Onslaught block. Ambush Commander, Elvish Vanguard, Everglove Courier, Gempalm Strider, Timberwatch Elf, Tribal Forcemage, Aphetto Dredging and Cover of Darkness may help you.
That's the idea of the deck--tokens to power Jagged-Scar Archers, with Coat of Arms and Overrun as finishers. It drops more threats than the opponent has answers, then Overrun+swing. Also, regarding Onslaught block, the tournament version of this deck was meant for Standard tournaments, meaning I cannot use cards from that block.
I say you remove what I told you, and go for token-making cards so that you can attack without fear once any of the power raisers comes. Now that I see it, shroud may help you. And I'm not sure if black should go at all. Check the Lowryn cards for these (I am not updated) but I would remove the black considering the cards you have in your deck.
Elves can be run mono-green or BG. Nath is the only good black elf, but the deck really needs the removal to get blockers and potentially harmful creatures out of the way. Also, the base of the sideboard is black. Thoughtseize is a fantastic anti-control card, and Deathmark is an excellent card against aggro cards like Tarmogoyf. It even works well in the Elf mirror; the Eyeblights usually go out for Deathmarks in such a case. Regarding shroud, that's why I play Steely Resolve; it gives all your elves shroud for a really cheap price.
Thanks for the advice though.