I'd be glad to help. As of now I'm below 2k from decay but I'm getting back up. Still, I like to think that I have some knowledge about how to play.
Fire start is not very good unless you have godlike micro and can kill the opponent before your low economy starts to bite you in the ass. You can fight second archer but you will sacrifice earths you could be using for miners, further delaying miner production. Greatest chance of success with fire start is castle.
Keep it to short maps of at all.
3 earths start is undoubtedly the best for any map. Turn 2 into miners, send one to middle. Usually you'll get pushed back to base. You can stall with earths and buy castle air if it becomes too overwhelming. 4 second que time is great. You can try and sucker the archer into getting close and double tap him with castle air. You'll most likely have more economy than him at that point.
Usually when your opponent turtles, it means you have the advantage. Don't give them the time to get back up on their feet! Charrogs can tank a lot of damage so you can destroy the walls, trees take a little longer, like a siege. The 3 other support combinations are great vs turtles once you learn to use them.
Charrogs are your stall/push unit. Don't rely on it to break a turtle that has been setup to a certain extent as it'll die so quickly that you would have been better sending the resources used, into a different unit.
Mid-game builds are really up to you.
The builds actually require you to go with at least one type of ranged unit. Preferably, fires with the ability to kite and burn damage shredding armor. Fires can lead to scorch when producing for trees and such. Airs are a bit more situational in sniping priority units if you wish to produce heavy amounts of them. Airs a more very fragile But don't use charrog + tree. Charrog and tree pressure isn't a good idea, it takes up a lot of resources, population and time.
the reason for this being true is that you have to spend at least one earth and one fire to make a charrog. Reducing your ranged presence for a melee unit that will hardly add any dps and will only last for so long. Burn damage or poison damage. Take your pick. Scorplings are weak against turtles and charrogs aren't much better with their weak melee.
against set-up turtles** Try to go for either charrog or tree with some range unit for the bulk of your army.
Charrog build is weaker since water heal is shit now. But it's usable. You can generally push farther into their frontlines with charrog. Trees require good placement and timing. Just make sure you aren't rooted up in your base the whole game, that's the worst way to use trees.
The worst way to use trees can also be the best way to use them. Imo. I never leave my base with my trees. It exposes them to too much from the enemy, that he/she could capitalize on. If my opponent has his miners in close proximity to me or I'm too close to his units in general he could rush my trees with units much more quickly as my scorps will autoRushdown his units or wall(s) without grouping. Which is very bad.Push up slowly, eventually you'll want to be near their second ring of gold. You'll need good timing though or your trees will get destroyed. Clear the way with support units.
Here's some builds that you can do:
http://forums.stickpage.com/showthread.php?86376-Elemental-Setups-by-Pumu
I find that fires aren't great for being a big part of your army composition. Their projectiles are slow and have short range. But they have their uses. If you're using a tree build, chances are the enemy will build lots of swords to chop them down. Burn damage can stop them in their tracks, maybe 1-2 fires can be good for protecting your tree and units. Their fire balls are armor piercing. They're strong defenders.
Fires can be produced gradually over time. Don't stop at just two lol. The more the better. Just keep a water handy. Your opponent will either be too afraid to rush your trees with the threat of scorch OR the opponent will attempt to feignt rush to make you waste it. In either case, only use the scorch when you see the Swords actually touching your units for the best outcome.
Airs are awesome, their lightning bolts come from the sky. You can even target archers hiding behind speartons. 3 lightning bolts can one hit kill an archer, 5 for an albow. Also armor piercing.
Nice units with speed but very fragile. Use them conservatively if at all.
Here's my opinion and personal tips about the rest of the support units:
Cycloids: Fast and tanky unit. Like your army's bodyguard. Strong against albows, you can tank for airs or fires and stun them for easy targets. 2 tornadoes are enough to wipe out archers, if you send in a team of cycloids you can sweep a bunch of archers. Protect is useful against shadows, you can use with water heal to minimize the damage your units take. Useful to help trees push forward or vs dangerous units like flyers and insta killers.
You generally want to use the protect ability on units that will be closest to the fray for whatever reason. Units that this applies to: Ts1+2, V(s), the cycloids themselves if attempting to tornado sweep archers or Rush albows. That's about it. Trees don't need it if you keep a watchful eye for shadow mass and respond appropriately.
Infernos: Personal favorite, UoMD (unit of mass destruction). Meteor upgrades are a must, fire rain is useless without meteors. These do an insane amount of damage and stay on the ground for a long time. Great counter against archers and spellcasters.
These units capitalize on the length of the map significantly. Less kiting space for the enemy and a shorter distance to their economy in which both the kiting units/mass/economy are your primary targets. Secondary targets= slow moving units that rely on being still to function. Ie merics.
Dragon spell is a little useless, but you can use it as a distraction. Or you can trap units, cast meteor rain on one side and dragon spell on the other, they'll have to choose their death. Meteors are also neat to trap units once they garrisoned. You can be more aggressive with charrogs since they can forcefully push forward, heavy damage. With trees you'll have to be more careful.
Vastolis deals heavy damage and forces movement whilst the meteor rain upgrade locks the position down for whatever area you cast it Down upon. Generally directly on or behind where your enemy is to force them to be closer to your units and possibly get clapped with scorch/poison/possess. Meteors can be placed in front of the gate to buy time to destroy the statue and punish them for attempting to run out with anything more than shadows and spears. In the case you know that your opponent is queuing shadows; you should be baiting the opponent into attacking you first with high priority units like V. Closing the game is usually the easiest with a few V's in conjunction with your fires/tree/water comp as it conforms the best to most order meta
V: A little pricey, but it's not hard to buy v.You need fast fingers. Possess is nice, don't try to take full control of whatever unit. Try to draw enemy fire on that unit you possessed, so your opponent ends up shooting himself in the foot whether they like it or not. Pretty nice against flyers. Teleport is neat, you can also teleport forward then possess whatever unit. Just make sure you can get out.
Best units to posses vs order:
Merics
Spears
Shadows
Magikill
Clones are probably my favorite and perhaps the most useful. V himself actually has really heavy melee damage, 2 hit an archer. If you upgrade your clones you can get that same heavy damage. They're very nice to push through, kung fu kick their frontlines and destroy walls with ease. Getting more than one v and cloning them all can have devastating results. You can mix your v in with the clones for maximum melee damage, but you'll have to be ready to get him out.
Avoid sending the actual v into the fray unless your absolutely sure that your opponent lacks the ability to kill him at a moments notice.
You can also go around this forum and read posts about elementals to learn. Helped me quite a bit. You can ask me any questions about elementals and I'll be more than glad to reply.