Battlemages suck. Bad. They have one playstyle, attrition, and that's not because it's good. It's because it's the least bad. They have not aged well, they have a really muddied theme in their spell selection, and they just feel bad to play.
Let's fix that.
Remove these spells:
Chill Touch
Shocking Grasp
Faerie Fire
Earthquake
Terra Shield
Force Field
Colour Spray
Air Shield
Reflective Shield
Sear
Flashfire
Why? Some are just awful. Some don't fit the theme of a practical magic user (BMGs are supposed to like efficient magic). Some violate both. And the rest are shields, which will be discussed further on.
Change these spells:
Rust
Sharpmetal
Meteor Swarm
Dancing Weapon
Blades
Rust - Increase success chance and penalty. As is, it's not worth the cast most times.
Sharpmetal - increase damage, but let AC reduce the damage (if it doesn't already, I gave up reading the BMG code, I don't want an aneurysm). Again, it's not worth the cast most times. Make it available early on to help ranking. Can make the damage scale with level (maybe make it projectile based, like throw, and have the damage scale similarly), I'd say around level 12.
Meteor Swarm - narrow the roulette a bit in terms of both chances and damage floor/ceiling. I'll be honest, I kind of want to remove it completely, but I recognize that many people enjoy this meme of a spell. And after all, the goal is to make the class enjoyable.
Blades - Increase hit chance by about 15%, and damage by about 10%, but let AC reduce the damage taken, in line with melee attacks. Drop to level 25.
Dancing Weapon: Here's the big one.... You can float one of these 3 options: a 2-hand, two 1-handers, or a shield. What this skill does changes based on what you choose.
2-hand: Same as is now
1-handers: More or less the same, but a penalty to attack chance in line with the penalty for dual wielding, and it cannot trip.
Shield: Extra defense. Shield will slam into anyone trying to bash/bodyslam/tackle/trample/etc you. This greatly reduces the lag you take, and also reflects damage to the user, based on their weight, up to a cap of 50% of the damage.
Add these spells:
Shrapnel Shield (20)
Bulwark (30)
Grind Metal (35)
Impact (40)
Focus Mind (50)
Shrapnel Shield: -AC equal to your level, reflects level/10 percent of damage taken back to the attacker, maximum twice per round.
Bulwark: -AC equal to level*3. Prevents Meteor Swarm from hitting you.
Grind Metal: Reduces the duration of your blades by 50%, but increases their damage by 25%.
Impact: Hurls a large chunk of nearby debris at the target. Deals less damage to the victim the larger they are.
Focus Mind: While the effect lasts, you get extra passive accuracy/damage on blades/dancing weapon based on your intelligence (Starting at 21, you get 1 bonus hit/dam, so at 25 int, you have +5 hit/dam with these spells). You expend the effect on your next cast of the following spells: Impact, Rust, and Sharpmetal. Once expended, you cannot focus your mind again for 12 hours.
Impact: Damage Has a chance to lag for 2 rounds (if it hits), equal to intelligence * 4
Rust: casts at +1 level per intelligence above 20 (so again, +5 at 25 intelligence)
Sharpmetal: Adds one additional projectile to the spell per intelligence above 20 (same deal as above). NOTE: These extra projectiles are not guaranteed to hit.