You though I gave up? No! I'm back and I have some news.
How to make game balanced? Teach computer to play it and see how it goes! I made a simple auto-player mode that plays until it dies again and again. Then I can see how far it went and analyze the results - e.g. if some monsters are too complex, or some warriors are too much invulnerable.
Game logic changes:
* Combats are now with some randomness. Fighters always lose health points as per the opponent "attack" value, but excluding the random value from zero the the current character "defence" value. That's why Archer is not invulnerable anymore, and characters with equal strength still can win the fight.
* Game is lost when at least one of the warriors dies. But that happens too ofter? Right, that's why they can are resurrected if possible. Warrior is resurrected at the end of the level if player has a certain amount of gold. Half of gold it spent on resurrection.
Finally, the browser version. It uses Pixi.js (yeah, WebGL is the best technology to display ASCII graphics, isn't it?).
Now user can undo the placing of warriors if he mistyped. And there is now an "info" screen that shows verbose information about the characters of the current level. And of course now there are colors!
I will upload a new browser version once I feel it becomes stable playable. Probably to a new location, so both version (one-day and seven-days) are available online.