Making some comments as I look through the article. Saying the weapons were replaced with ones with different abiltiies is inaccurate; the weapon abilities already vary both by type standards, and with some individual variation.
To my eye; the problem with the weapon system wasn't so much the hard to tell number; but UI flaws: while the first number ni your armor was piercing defense; that was never explicitly said, so people didn't know what their pierce defense was. Second; the effects of armor were never made clear within the game itself in any place I know of. This made it hard to figure out how much armor was going to reduce yoru damage; especially with some of the weird rounding effects: since it always rounded down; a 4 damage weapon vs a 5 armor target (a common occurence if you make a 4 damage militia vs any unit that has no defense; it'll have 5 when it defends); you do 0-1 damage in that case; the formula comes up with iirc 4/9 * 4 = 16/9; soo 8/9 to 16/9 damage; so it gets 0-1 after using the always round down system.
Until I read the armor system on the forum I had trouble figuring out how armor works; this again is a failure in the ui rather than a failure of the damage system; a clear UI with appropriate tooltips would have made this all entirely clear to all the users. Also I concur with others points that there's a lack of armor choicse in fe that really let you itemize against certain damage types; and the weapon selectyion is a little thin due to too many of the weapon abilities being too weak.
Hero changes sound promising; but hard to tell in practice; having a fleshed out tree is certainly useful; the only question is whether it will allow for enough variability in gameplay to be interesting; or if things will too readily devolve into giving the same heroes the same build over and over again.
This reminds me of one of the fundamental flaws with a game called Battle Dex; an online ccg/ tactical war game. There you hads 12 cards; and all were available from the start to play. While it's nice having accses to all your cards; it makes the game play very similar from game to game as long as you use hte same deck. While things may play out somewhat differently depending on map and what your opponent does; there's still a strong sense of similarity from game to game; especially as a number of cards are things that are equivalent to low-cost summons. This means that you may use half your cards up before you even see the enemy; and having a standard open like that means there's a lot less choicse to be made.
I think there will be enough variability with found items or game considerations changing what you do; or just having enough heroes, but it's something to keep an eye on. Another example is Vow of Poverty in d&d 3.5; which gives mad bonuses but means you can't use any magic items, and barely any mundane ones. While it's effective; sometimes people remark on it being boring as you know EXACTLY what your char is gonna look like as they level up
Other stuff sounds promising, as long as its' well balanced, which should be rather feasible. Will weapon abilities change in the base game to match the new system at all, or receive other changes to fix the current balance issues with them?