Mr X, the more I've thought it through, the more I think having some weapons act as spell focuses could be a good way to jam in some character specializing. The weapons that are strong against a certain enemy type are almost always unimportant (or maybe literally always unimportant? I only care about status effect procs personally), and there's generally multiple weapons with the trait for a given enemy type, so tying the enemy type weakness to either a certain element, or a certain type of spell could be a good route. An obvious one is the strong against undead weapons for turn undead (just revivify in general to remove the need for a mana cost reduction), though I'd like it to affect at least one spell for the sprite. Doing the same with anti-animal, -slime, -insect, -dragon, etc. would potentially give those weapons better purpose, and since the point is to benefit spell casting, them having bad attack power wouldn't be critical, and there being multiple weapons per trait means you can choose a weapon type you don't personally find fun to sacrifice as a spell focus.
For the Rising Sun, and I think it's two other non-level-1, non-level-9 weapons without any special features, I've always meant to just give them something. I've wanted to see how overpowered engulf would be on the Rising Sun.
I'm rather tied up this week, so it'll be a bit before I can really get anything ready for testing, but I've been considering the approach I'd take to implementing this stuff.
I always like to use the Herald Sword (effective to Lizards) on Jabberwocky even tho the damage seems the same probably because it's type was changed to Dragon, making the weapon really only useful on one mob lol. Same with other weapons the Dragon weapons for Pure Land Dragon bosses, and the Anti-Undead and Insect/Metallic on the Empire.
Adding another purpose to them would be very cool, as you said I personally stick to status infliction weapons, endgame I reforge some weapons to inflict Poison and Balloon those combos are so OP I never have to use spells for mobs.
Rising sun with Engulf might be worth a try to see how it fares probably will turn into a very strong weapon. There is also the Steel Lance and Javelin (both level 2) that do nothing, probably have them inflict Mired status?
Besides the Weapons effecive on certain enemies giving them more purpose, I would maybe take a look too at the agility/weapons that inflict slow, I don't think I have ever seen a noticeable use for them.
Constitution boosting Weapons - reduce MP cost of Wall (increasing the base MP of that spell)
Strength boosting Weapons -
Crit Rate boosting Weapons -
Agility Weapons -
Weapons that inflict Slow -
Int/Wisdom Boosting wWeapons -
Anti Plant/Fish Weapons -
Anti Slime/Lizard Weapons -
Anti Insect/Metallic Weapons -
Anti Undead Weapons - reduce MP cost of Turn Undead (of course increasing it's MP cost) and Lucent Beam just makes so much sense here.
Anti Dragon Weapons -
Rising Sun - Inflicts Engulf
Steel Lance - Inflicts Mired
Javelin - Inflicts Mired or Balloon but have a later weapon inflict Mired because of how OP Balloon and Poison are.
Herbal Boost, Wall, Lucid Barrier, Balloon, Blaze Barrier, Saint Saber, Flame Saber, Black Hex/Hellfire (depending which one you use), are possible other spells that might be good to get an MP increase but with certain Weapons get then their MP decreased.
As for Armors more thought need to be put into it but another idea that I had in mind is give Gold Bracelet the ability to increase the rate of the rare items you get from Enemies so you are more encouraged to farm yet not be as tedious to get certain items that you want, but get them actually through gameplay. That is if it's even possible to do that.