BE may ignore limitations for the enemy team, it actually does so in many games. That's why in jrpgs enemies never run out of mp, or in shooters with limited ammo enemies have unlimited ammo. Because often there is no way for them to replenish it, unlike the player.
We don't have that but it's not hard to arrange...
There is another issue thought, with default attack type. If a character has a weapon on the battle sprite, then her basic attack should not be default fists, but the weapon she has. Therefore we need a field for basic attack (without weapon equipped) in character data files, which by default will be fists.
We should already have that.
That's not about classes. Agility increases infinitely for any class, given time and/or levels
No, base classes can stop that, slow it down or increase the rate it's gained on level-ups.
And if you want to replace resistance with intelligence, then we already have tons of magic related things tied to intelligence due to lack of magic defense stat.
But is it not how you make the battle engine interesting. Weird enemy that cannot kill your party while endlessly evading it would be very unique, we could cap the the amount of max turns for BE, with battle resulting in a draw or something. Unique stuff is allowed to be annoying. We can also add running away option.
And if you want to replace resistance with intelligence, then we already have tons of magic related things tied to intelligence due to lack of magic defense stat.
I don't think that would be a bad thing. Not mentioning that I've already told you that I consider the whole magic resistance thing a bad idea, twice that much if done through a new stat.
My approach would have been a new status skill that partly shields from magical damage for x number of turns. I like and understand evasion from weapon attacks. I like resistance to elements, maybe to magic itself. But I don't get random reduction of damage based of a stat/health. I liked older system way better, it was more intuitive and could have been great just with better balancing.
It also give me an option to make some items and traits better or worse by adding bonuses and penalties to the new stats. While giving bonus to intelligence pretty much increases everything about magic, bonus to resistance only increases resistance.
Yeah, and that is exactly what I meant with new item "be" field. We can add stuff there effecting BE only. I mean, the thing that hurts me the most is that I've spent many month trying to develop a system that could create chars/mobs that would feel different from one another in the game/BE and you've basically said: Fuck That Shit! We're gonna add new stats that do not change and your Chars will have the same evasion at level 250 as they had at level 1. Not learning how to dodge anything in between.
Some spells can be dodged, depending usually on animation but that will be close to impossible to balance properly cause we don't draw animations ourselves... but:
defense = round(target.magic*0.2 + target.defence*0.6 + target.intelligence*0.2)
This seems like a reasonable magical defense setup, why do we need more? The whole resistance thing feels like really off

We already have elemental resistance, damage reduction, base traits controlling development of all of these stats and will soon have item mods... maybe more trait mods in the future. The more I think about these two static evasion stats, the more I hate them

Hm? There is no "melee" + "magic" + "fire", such combination is impossible. I can't even imagine how to use one if it will be added
I thought that was what you were asking me to add

So basically let's say I add there a new keyword, like "magic_weapon", which will lead to some another formula of attack and defense calculation, making magic a bit more useful for some (not all) skills. Because otherwise magic is pretty useless for pure warriors. That's the plan at least 
But that was the whole point! Magic not being useful for pure warriors other than defending against it a little bit. That's how we differentiate between different case classes.
I just checked with traits_class file. You mutilated my Battle Mage class

The idea behind it was a class that would have moderate increases to mp/hp/magic/attack/defense. Kind of a jack of all (combat) traits (except agility) but kind of none. While Warrior would completely suck at mp/magic, mage would have shitty defence and attack but really high mp/magic, archer would have very high agility, moderate attack and very slow magic/mp and etc.
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I don't like magic weapon either.... I don't really like anything that would combine magic and attack into a singe damage formula. It kinda completely erases difference between magic and non magic combatants.