Now assuming that DM's here are okay with the class, I'd be quite happy to make this class for ALFA once we're all updated to the latest patch. If there are any tweaks the DM's want then we can fix that up as well

Below is the reworked Bladesinger PrC. I streamlined the entry requirements (still not easy to get into.) Spellsong of Celerity now looks more like Daggerspell Fury or a 3.5e version of the RoF Bladesinger. Bladesong Master now adds full Dex to melee damage. I added a specialist style restriction to the Bladesinger, the cost of mixing spell and sword is fairly hefty, but I think it's warranted due to the relatively good spell progression, decent hit die, high BAB (think of the (ranged) touch attacks and the theoretical spell selection), two good saves and all.
Comments and suggestions appreciated.
Spoiler:
Hit Die: d8
Entry Requirements
Race: Elf or half-elf.
Base Attack Bonus: +3.
Skills: Balance 2 ranks, Concentration 4 ranks, Perform (sing) 4 ranks, Perform (dance) 2 ranks, Tumble 2 ranks.
Feats: Combat Casting, Combat Expertise, Weapon Focus (longsword, rapier, short sword, or scimitar).
Spells: Ability to cast 1st-level arcane spells.
Class Features
Weapon and Armor Proficiency: A bladesinger gains no weapon proficiency but does gain proficiency with light armor.
Spellcasting: At each level, except for 1st, 5th, and 10th, a bladesinger gains new spells per day (spells known if applicable) and an increased caster level as if she had also gained a level in an arcane spellcasting class she belonged to before entering the bladesinger prestige class. She does not gain any other benefit that class would have gained. If the character had more than one arcane class before becoming a bladesinger, she must decide to which class she adds the new level for purposes of determining spells per day.
Bladesong Initiate (Ex): Upon becoming a bladesinger, the character chooses one weapon for which she has the Weapon Focus feat used to qualify for the class to become her favored weapon. If a bladesinger has more than one applicable weapon, she must choose one. A bladesinger cannot change her favored weapon once she makes her choice. A bladesinger receives a -2 penalty to attack with all weapons other than her favored weapon.
When wielding her favored weapon in one hand, nothing else in the other, and not using a shield, a bladesinger is in the bladesong stance. A bladesinger must use and benefit from the bladesong stance to gain any benefits from the bladesong and spellsong abilities of the bladesinger class. If the bladesinger wears medium or heavy armor, she loses all benefits of the bladesong stance.
When in the bladesong stance the bladesinger gains a dodge bonus to Armor Class equal to her class level, up to a maximum of her Intelligence bonus.
Spellsong Magic: A bladesinger dedicates herself to mixing magical and martial skill into a harmonious art. As a result, when the character becomes a bladesinger, she loses the ability to learn any new evocation or necromancy spells just as a specialist wizard would. (though she retaints the ability to cast spells of either school already known)
When a bladesinger uses a spell for any of her spellsong abilities, the spell gains a verbal component. Spells used for spellsong abilities cannot be enhanced by the Silent Spell metamagic feat or have their verbal components otherwise negated or countered, such as under the effects of the silence spell or if the bladesinger cannot speak.
Spellsong of Focus (Ex): A 3rd level bladesinger can take 10 when making a Concentration check to cast defensively when in the bladesong stance.
Bladesong Adept (Ex): When in the bladesong stance, a 5th level bladesinger ignores arcane spell failure chance when wearing light armor. Additionally, she can also use her favored weapon to do piercing or slashing damage, but not both at the same time.
Spellsong of Celerity (Ex): At 6th level, a bladesinger can quicken one spell as part of a full attack when in the bladesong stance. Doing this has no effect on the spell's effective level. A bladesinger must make at least one melee attack in any round in which she uses this ability, and he cannot make an attack with anything other than her favored weapon (although if a spell cast in conjunction with this ability requires an attack roll, she can still make the spell's attack).
A bladesinger can use this ability a number of times per day equal to 1 + her Charisma modifier (if any). A bladesinger gains an additional use of this ability at 9th and 12th level.
Spellsong of Presence (Ex): A bladesinger of 8th level can expend a spell as a standard action to use Perform (Singing) in place of Intimidate for a number of rounds equal to 1+ her Charisma modifier (if any). The bladesinger gains a bonus on Intimidation checks equal to the spell level expended. A bladesinger may only use this ability while in the bladesong stance.
Bladesong Feat: A 10th level bladesinger receives Bladesong Style as a bonus feat. If she already has the Bladesong Style feat, she instead selects any feat that has Bladesong Style, Combat Expertise, or Weapon Focus (bladesinger’s favored weapon) as a prerequisite.
Spellsong of Fury (Ex): At 13th level, when a bladesinger makes a full attack while in her bladesong stance, she can make one additional attack in a round at her highest base attack bonus, but this attack and each other attack made in that round takes a -2 penalty. This penalty applies for one round, so it also affects attacks of opportunity the bladesinger might make before her next action. If the bladesinger makes the full attack using spellsong of fury in the same round she successfully casts a spell using spellsong of celerity, the bladesinger only takes a -1 penalty to all attacks for the round.
Bladesong Master (Ex): A 15th level bladesinger adds her Dexterity bonus to melee damage when in the bladesong stance. She also gains a +2 competence bonus to disarm and trip attempts with her favored weapon.
Class Skills (2+ Int modifier): Balance, Concentration, Craft, Decipher Script, Diplomacy, Jump, Knowledge (arcana), Perform, Sense Motive, Spellcraft, and Tumble.
Code:
Table: The Bladesinger
Level BAB Fort Ref Will Special Spells per Day
1st 1 0 2 2 Bladesong initiate - -
2nd 2 0 3 3 +1 level of existing class
3rd 3 1 3 3 Spellsong of focus +1 level of existing class
4th 4 1 4 4 - +1 level of existing class
5th 5 1 4 4 Bladesong adept -
6th 6 2 5 5 Spellsong of celerity 1/day +1 level of existing class
7th 7 2 5 5 - +1 level of existing class
8th 8 2 6 6 Spellsong of presence +1 level of existing class
9th 9 3 6 6 Spellsong of celerity 2/day +1 level of existing class
10th 10 3 7 7 Bladesong feat -
11th 11 3 7 7 - +1 level of existing class
12th 12 4 8 8 Spellsong of celerity 3/day +1 level of existing class
13th 13 4 8 8 Spellsong of fury +1 level of existing class
14th 14 5 9 9 +1 level of existing class
15th 15 5 9 9 Bladesong master +1 level of existing class
Bladesong Style [General]
Prerequisite: Elf or half-elf, Dex 13+, Combat Expertise, Weapon Focus (longsword, rapier, short sword, or scimitar).
Benefit: You only gain the benefits of Bladesong Style when wielding a weapon, which you have Weapon Focus for (longsword, rapier, short sword, or scimitar), in one hand, nothing else in the other, and not using a shield. At the start of each encounter, you pick either the offensive stance or the defensive stance as a free action. If you chose the offensive stance, you add +1 to melee damage. If you chose the defensive stance, you gain +1 Armor Class when fighting defensively, making a total defense action, or using Combat Expertise. You cannot benefit from both bonuses at the same time, though you may switch between them as a swift action.
Special: A fighter may select Bladesong Style as one of his fighter bonus feats.
Advanced Bladesong Style [General]
Prerequisite: Elf or half-elf, Dex 15+, BAB +8, Dodge, Bladesong Style.
Benefit: When using the Bladesong Style feat, you gain a +1 bonus to attack in addition to the regular bonus if you chose the offensive stance. If you choose the defensive stance, in addition to the regular bonus, you can chose to have the Armor Class bonus from the Dodge feat applies to all opponents or the bonus against a single target increases to a +2 bonus to Armor Class.
Special: A fighter may select Advanced Bladesong Style as one of his fighter bonus feats