RolledAOne

To help keep in standard I would go with 4 Elvish Mystic. There was also that R/G druid that taps and deals 1 damage. For walkers I would go add in another Kiora and Nissa (seeing as she is part of your infinite combo and is decent end game). Your control spells and everything seem to be fine. You could also add in that blue spell that turns all of your oppenents creatures into 1/1 frogs, Polymorphist's Jest. That would work with Anger of the Gods (yes I know its a 6 mana total but hopefully it won't be a big deal with Nissa and ramping).

You will need to do some heavy playtesting to.

This isn't too bad at all. I would recommend that you go to 24 lands and add in 2 more walkers so that you will be able to draw them. Also maybe another set of mana dorks would be good to.

I'd add in more haste givers and evasion type cards. Bladed Pinions, Whispersilk Cloak (it was printed as a common), Strider Harness, and Fleetfeather Sandals.
Trample and some buffs would go nice too. Runes of the Dues should be a must in this deck.
Bloodrush cards could alao be nice.
Also maybe add some instant speed potection like Vines of Vastwood or Withstand Death or Ranger's Guile.

I have a Heartless Summoning deck too. Big thing you want to do is have some removal. Since you are playing blue you have access to counter spells and bounce spells. Also even though you have reduce cost for casting creatures you might want to add in 2-4 more lands. I've found this to be better for my higher cost creatures and if I don't have Heartless out for whatever reason I can at least have a reasonable chance to play without it.
Rune-Scarred Demon should go in here for sure. Great tutor and its a beatstick with flying.

So what is the main point of this deck? I can see what you want to do but at the same time you have cards that keep you away from that goal.

You could use some board wipes, spot removal, mana ramp and mana rocks possibly. Also maybe cards that can make use of your general's +1/+1 counters.

You might find Tribute to the Wild useful.

Here. A buddy of mine was going for a legendary type deck.
http://www.mtgvault.com/ktrojan/decks/legenwait-for-itdary/

This isn't a real deck. It's just commanders they are interested in playing.

You know Vess has been in other sets. You can add them in.

This is a deck my buddy made. Look it over and it should give you some ideas on what to use. http://www.mtgvault.com/ktrojan/decks/the-commander-deck/

You should really cut some of the 1-ofs you have in this deck and add in more 3/4-ofs a card. This deck is too random (which if you like to play it that way then go for it). However you are in green and mono-green at that. Just go down to 20-22 lands and add more ramp spells into the deck.

This deck could use more removal I think. You are gonna get shut down pretty hard.

Two things you are missing for sure. Mikaeus, the Unhallowed and sac outlets.

I would go with Yukora or Halfdane, Both can be pretty straight forward or you can do some neat tricks/combos.

Go with the Iguanar, you do have Beastmaster in but to be honest you most likely won't be attacking much. Or personally I would run 3 or 4 Purphoros. You have a better chance to draw him and if he is part of your wincon you should want him out.

Add in changelings. They count as Atogs. One of the best ones you can add would be Mirror Entity and Chameleon Colossus.

I have a cleric deck that uses him and I put in a sac engine to make sure that they die. Otherwise from my experience either nobody will attack you unless they can get around it or kill you that attack. Otherwise they will just exile it some other way.

From what I see you can replace Seal of Cleansing with Aura of Silence. Does the same thing but for 1 more white mana and an added bonus. I would most likely replace Celestial Archon with Sun Titan or now that I think about it you might be better off adding in Kor Spiritdancer (totally forgot about that card). That would give you more draw and another beefy creature with all the enchantments.

Mistveil Plains can help you put graveyard enchantments back into your deck. Add in Enlightened Tutor and/or Idyllic Tutor to really help you fetch them back out.
Sun Titan would also be a good creature to add. Help you get your CMC cards back on the field and can be a good beatdown card.
If you do plan to keep in Academy Rector you will need a some way to sacrifice them. High Market is always a good card to add.
Aura of Silence is a good enchantment to help slow down your opponents and if they try to remove it from game you can just sacrifice it instead.

This seems like it will run smoothly in multiplayer, has a nice curve and good synergy.