I hadn't gotten around to writing this, but if anyone have considered improving 2-Handed Weapons (particularly Axes), then here are some ideas you may want to play with.
Note: I will use the axe as a reference, for the sake of pointing out that the Poison and Rune Axe suck, relatively speaking.
1) Increase defense - Make it so that say 1/8 of the axe's attack power increases the defense of the character. This tends to increase the defense power of the character enough to take less damage, but doesn't help if you go full heavy armor (think of Kain or Cid, since Cecil has lots of Wizard armor alternatives). The defensive impact is minimal late game though since the defense multiplier and evade become more important. Compared to shields, shields provide mostly evade than defense, so that's the unique swap there. Note that the strongest possible axe you can create will increase up to 31 defense, which does have a nice impact there (it's good if you don't plan or don't want to use defensive race properties in the armor). You will still be taking damage though...
Edit: Changed 1/4 to 1/8 instead.
2) Increase evade - Make it so that say 1/4 of the axe's hit rate increases the evade of the character. This helps a lot when shields are the greatest factors in increasing defense via evade. The highest you can get here is 24% (or maybe more, but someone would have to make this code first to test it out)), which is far less than the best shield in this game (FF4, not FF4A) can provide (40% evade for the Crystal Shield), but still not be that overpowering. Note that the hit rate does have to be reasonably high or it will suck. The Hand Axe is not a good weapon if that was available when you have Cid, only because its pathetic hit rate will do below average damage for Cid vs his very accurate hammers. Trading evade for an underpowered Cid is a terrible option IMO. If the evade bonus can go up to 63% evade, there can be problem balancing this...
3) Increase defense multiplier... - Make it so that the axe is classified as a shield, so the defensive multiplier bonus of level/16 is applied. This is a bit more effective than increasing defense, although it has the same evade constraint problem. I've found that the Heroine Robe/Minerva Bustier has gives Rosa+Rydia near physical immunity in the Lunar Subterrain late game (particularly if you are stat boosting post level 70). Even if they have a high defense multiplier, it doesn't counter the low evade.. which is what the Heroine Robe provides (40% evade is not something to scoff at). This seems like a safer/the safest bet to change...
Here's a brief review/overview of having a 2 handed weapon vs a weapon+shield combo...
1) Lowered defense - A shield provides some semblence of defense, but not a lot in comparison to the other details.
2) No shield multiplier bonus - this is what the shield thrives on to be very useful. In the late game, this becomes very huge in terms of bonuses.
3) Lowered evade - The evade is where the important calculations are at. Increasing this helps more significantly in conjunction with a high defense multiplier which has the greatest impact of reducing overall intake of damage.
Standard counters to fixing this (assuming you are not trying out my ideas)
1) Increase Agility - Since the defense multiplier is derived from this stat, increasing this will have the greatest impact... +15 to Agility will nearly guarantee a 2x defense multiplier bonus. However, this also makes the character go significantly faster, and that may need to be accounted for in monster balance. Note that late game that Agility can be maxed by most characters...
2) Increase Vitality/Stamina - Given that defense is worsened, you can attempt to compensate it here. The best case you can do this is to boost +15 to it and gain +7 or +8 defense, which isn't really significant, though it can counter only the defense loss that a shield provides (just not the multiplier or evade though). This has minimal impact overall, although most characters don't ever really max this stat out (except for Cecil) because Agility has a far greater impact in this game.
Ok, thoughts, constructive criticism, and mentioning stuff I didn't consider is appreciated.