Don't bother with melee, FIMA punishes the melee playstyle. In basic melee fights you are forced to trade blows with enemies and with each new chapter enemies hit harder and harder but your armor can't keep up, you will end up taking too much damage from each encounter and slowly but surely lose. There are ways to make melee work (like bolas kiting, armband, chillkiting, ranged melee + haste/flow, etc) and deal one-sided damage but it's more practical to just play ranged
Ranged runs inherently don't have to trade blows, for the most part they will hit enemies from afar and kill them before they can get close and scratch you. I think the two easiest ways to win fima are sniper with upgraded throwables, and wandmonk
trickshots let you deal onesided damage even to ranged enemies, you can see how to do trickshots in supernewb's megaguide: https://drive.google.com/file/d/1j8pa2K4KJMtdNX8TQkIPONBrwdlMwSJE/view?usp=drivesdk . Trickshots will usually you get two-three hits in before any retaliation from the ranged enemy, if your wand/throwie is strong enough that may be enough to neutralize the enemy with no damage taken in return. If it's not enough then you'll have to get creative
Forgot to say that I am playing Duelist.
I tried going for evasion but did not manage getting beyond +6 armor. I was getting hit often enough to run out of health. But it was not a very lucky game in terms of support.
Barkskin warden can still melee with a reliable way to make plants for barkskin refresh. You can basically ignore FIMA once you get the mask as long as you can keep your barkskin up. I'd assume living earth mage can do something similar with rock armor.
Most of my challenge run and ascension are archer/sniper. I will use my first Upgrade scroll in a pot and make Enchantment stones, using one on the bow a saving the other.
If you can't purchase, or find an Augmentation stone, use a Transmutation scroll in a pot. Augment your bow for speed. Multiple shots at a distance along with the enchanted effect works very well.
If you are lucky to get a Ring of Might, use some Upgrades on it. Eventually you will get into mêlée and want to punch hard and fast.
Ring of Evasion with a few upgrades, and cloth armor with Stone enchanted also works well if you can get the right luck.
The best strategy for this challenge is to avoid taking damage for melee enemies. There are some tatics.. the most useful is to find a Ring of Speed + ranged weapon augmented for speed attacks. It requires a bit of luck but you can achieve this combination by other ways, like flux enchantment (that one the makes you fastest on water) + ranged weapon or projectile enchanted weapon.
Relics that creates distance between you and enemies are also high valuable (Bracelet, Hourglass, Ethereal Chains [GOAT])
Indeed there many forms to loose enemies, but what you need most is a ranged weapon.
The Runer Spec is a bit good for creates distance while on runing stance, and the aditional evasion can save you from unexpected hits (dont abuse it, the evasion will not save you as much as we think)
I respectfully disagree about only using throwing weapons, because at hight levels they dont do much, soon or later you will need a good weapon
Addtional coment: If you have a ranged weapon, and if you could see enemies behind doors or grass you can hit them. You can gets this vision for Huntress talent (quite op), Talisman or mind vision pot. The door must be open, and if you can postion yourself out of the enemies sight you will hit suprise attacks every hit.