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My temple paladin bring the temple on turn1 and gear up for melee. On turn 3 I bring a level 3 buddy (usually a Temple High Guard). since my melee build bring most of the heavy equipment on turns 4-7, usually I just cast clerics on turns 5 and 7. Then I bring a 2nd or 3rd level creature for reinforcement every other round (sometimes I wait an extra round or two to bring a bigger creature).
It is sort of a melee+reinforcements build

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But a gator toughness or even better, a glancing blow would. How many sp are you willing to spend to drop a 6 mana qcd lvl1 creature? One force push and im ahead in sp agaist anything but a FM

If you cast gator toughness on it, it becomes a 10 mana and 2 quick actions that costs 2 spellbook points. Against a warlock, it might be a flameblast rather than a force push, and then gator toughness might not be enough.

Tataree's mana generation is nice, and his defense might be useful in removing guard (would remove on average 6 guards before his defense will fail and the counterattack will kill him). Useful to counter these gargoyles, guardian angels and panzerguards.

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I don't have a best mage, I usually win with all mages.
I like most the holy mages and the forcemaster, with the straywood not far away from them.
I dislike the necromancer, even though I won all 5 games I played one, and won against it 4 out of 5 games. Even though I know how to counter him, using him still feel like cheating. I hate zombie necromancers more than I hate skeleton necromancers.

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In the Attack Procedure chart in the official supplement on page 3, the backgroundcolor of the cell "avoid attack - other attacks" (which includes the attack of hydrothermal vent) is yellow. According to the statement above this means that the defense step is part of the procedure for the attack type "other attacks".
Therefore the attack of Hydrothermal Vent and trample attacks can be avoided with every defense!

Now about trample, I think t does count as melee attack, but simply isn't affected by melee +x trait. So if a defende can't defend from melee attacks then it can't defend from trample.

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Well,  I like to play both of them with a temple as well.
I will compare them by categories:

1) Melee -
The priest is about burning enemy creatures, while dazing and stunning them so they wouldn't damage the priest while the burns do their work. I've seen priests using that bow, but I've never seen a priest with that bow winning a game, as the lack of daze and stun chance just ruin that strategy. So priests should use the Staff of Asyra, which is an amazing weapon.
The paladin melee just go for tons of damage with his challenge ability. unlike the priest that go for a medium amount of damage but great conditions, the paladin deal a great amount of damage with medium conditions. That's a totally different strategy.

2) Training -
The priest have access to the crown of protection, that allow you a really nice 2 mana spell for the round you would like to save mana for a big creature in a later round (or round when you lack mana because you just summoned something big). Giving an armor +1 token is like giving a creature a leather piece, except it doesn't use spells from spellbook and doesn't take slots (and can't be dissolved). It also combine really well with angels.
The paladin have access to balista, a very good conjuration, especially when combined with a temple of light. The paladin also have in school spells like akiro's favor, and having at least 4 copies of this spell allows you to give a reroll to many of your creatures.  An akiro's favor goes well with every creature that roll at least 5 dice (including knights of westlock, crusader griffons, Alandell, Ehren and some others). It's also really cheap to use on creatures other than your mage (only 3 mana). The champion's gauntlets are also a wonderful spell the paladin got access to.

3) Creature buffs-
The priest got the holy avenger ability, and it a very nice ability. The +5 life bonus combines well with the armor+1 tokens you can grant from the crown of protection. It also let you buff a creature greatly even when it didn't cost much to include him in your book. For example, let's start with a white cloack knight, a 2nd level spell. Now lets make him a holy avenger and give him an Armor+1 token, and we get a creature with 13 life, 2 armor, an attack of 4 dice that can be increased to 6 piercing +1 against enemies that attacked this round, and he is even immune to attack spells (for just 14 mana and 2 spellbook points).
The paladin have some awesome auras that benefit the creatures in his zone. The problem is that you need good positioning to keep them in the same zone as your paladin, but things like melee+1 piercing+2 to every creature in your zone is pretty awesome.

4) General abilities-
The priest have its creature do defend itself, while the paladin is there to defend his own creatures.
The priest have a holy avenger that get a bonus against an enemy that attack the mage, and the priest also daze his enemies so they couldn't attack him back. The paladin have an aura that allow him to take damage instead of his creatures, and if his challenged enemy attack a target that isn't the paladin then the paladin gain valor from it while the paladin allow his challenged enemy to get the same rerolls he get while attacking the paladin and not his creatures.

Overall. these are two very different melee holy mages, and I really like both of them

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So far, this opening with 3a was a fast enough response to early aggression. Once it will fail me, I might change it.
In my local meta, turn 2 aggression usually don't deal enough damage to seriously threaten on the 2nd turn, but is a beginning for a more serious aggression on the following rounds. Against such aggression usually the panzergarde+defend on turn 3 is enough, and the goblin grunt is a 3 dice attack until my opponent take an action to get rid of him (which is an action not spent on attacking my mage).

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I didn't play this match yet, but if the main problem is weak condition markers, then should the Cleansing aura help a lot to counter it?
It allows as a quick healing spell for 1 valor to heal a creature 2 damage and remove a poison condition by paying it's removal cost.
I usually carry one purify as well (because getting rid of poison blood and ghoul rot as a quick action if nice, and I rather spend my full action on a melee attack rather than remove curse).
Beside, against mages than use their full action on attacking rather than casting spells, gate to voltary is a little less effective (for getting only 1 mana per round from opponent casting). At least that was the way it felt against other melee mages, I didn't try it against the paladin yet.

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I think the mind school is more about psychology than logic.

About the leadership of sortilege, probably the leader actually spend most of his time on arcane studies and have ministers that know what their doing. Sort of like the supreme commander of USA army is the president, who usually have no knowledge or experience in battlefield strategy, but the ones that actually run the army are the generals.