I think PrCs are a fun addition to D&E 3.5e, and should typically be a fun and viable option for most character builds to further specialize their characters.
The influx of great new feats such as the recent epic combat feats has been a huge boon to the server. Unfortunately, this has also had the unfortunate side effect of tilting the scales too far towards favoring purist builds with 1-2 level dips that are able to accumulate loads of bonus epic feats and putting PrCs out of favor.
There are many PrCs on the server. Some are already extremely powerful and are taken regardless of the introduction of new feats while others are so weak that they are pretty much never taken outside of a few niche scenarios or as a minor dip. This post list what in my opinion are PrCs that fall into these categories, and will also list PrCs that can be brought up to par with some relatively minor tweaking.
Top Tier. These PrCs are already a shoo-in for most relevant builds and are already readily competitive with pure builds. No changes are suggested.
Arcane Archer
Arcane Scholar
Child of Night
Hellfire Warlock
Marksman
Pale Master
Red Wizard
Invisible Blade
Mystic Theurge
Sacred Fist
Stormlord
Stormsinger
Mid Tier. These PrCs are very decent, but are generally slightly weaker/inferior to a pure build. Adjustments are suggested for each case.
Blackguard
With the introduction of the Epic Combat X line of feats, the Blackguard faces an identity crisis. While the core of the class is good - sneaks, high BAB, proficiencies, turn undead and an aura, the bulk of the power is found in the first 3 levels and it's generally taken as a dip in a caster build. Pure martial builds generally avoid Blackguard as it disqualifies your build from getting the purist bonuses from the Epic Combat X feats while caster builds will dip 3 levels.
Suggestion (quoted from Discord):
Introducing epic feats to improve the Hexblade/BG curse aura would make Hexblades and pure Blackguards a lot more useful than they are now. These could include something like the following:
Intensified Aura of Despair
Type of Feat: Epic
Prerequisite: Cha 25, Improved Aura of Despair, Blackguard 10 or Hexblade 20.
Benefit: Your aura of despair inflicts a -3 penalty to the AC and AB of all affected creatures.
Greater Aura of Despair
Type of Feat: Epic
Prerequisite: Cha 25, Intensified Aura of Despair, Blackguard 10 or Hexblade 20.
Benefit: Your aura of despair inflicts a -20% penalty to all damage immunities of affected creatures.
Bladesinger
This class has been tweaked extremely heavily but is still generally ignored. This is due to the relatively high cost of entry, the uselessness of the song of celerity/armored caster features in ROT, the lack of any bonus feats, and also the highly questionable 5/10 casting progression of the class.
Suggestion:
2) Allow the class to progress bardsong levels
3) Improve Bladesinger spell progression to 9/10.
Canaith Lyrist
This PrC is actually pretty good. The only problem is the lack of any access to purist caster feats limiting build possibilities.
Suggestion:
1) Allow builds with 15+ levels in Canaith Lyrist to qualify for the epic purist caster feats.
Champion of the Wild
This PrC is generally only taken as a 2 level dip to add Dex bonus to AC in a weapon finesse build. It however has rather strict entry requirements that oddly include the need for Heavy Armor Proficiency.
Suggestion:
2) Make the level 8 Wrath of the Wild ability a passive bonus
3) At level 10, gain Improved Wrath of the Wild where the bonuses are doubled.
Duelist
Generally designed for Swashbucker builds, this class is neglected due to no progression of sneak with Daring Outlaw, no bonus feats, and no significant bonuses outside of an AC boost.
Suggestion:
2) Duelist levels stack with Swashbuckler levels for purposes of Daring Outlaw sneak calculations
3) Increase the damage of Precise Strike from 1d6/2d6 to 1d12/2d12
Dragon Disciple
This class is very close to being good and extremely flavorful. However, like Blackguard, it suffers from an identity crisis as it disqualifies you for Epic Combat X purist bonuses, is Medium BAB, and the Stat bonuses fade in relevance at higher ERs.
Suggestion:
3) Give the class 8/10 spell progression
Eldritch Knight
Like Canaith, I think the only thing lacking here is access to Epic Purist caster feats.
Suggestion:
1) Allow builds with 15+ levels in Eldritch Knight to qualify for the epic purist caster feats.
Elemental Archer
It provides decent passive buffs, but is generally overshadowed by other ranged classes.
Suggestion:
2) Improve Elemental Storm to match Arcane Archer Hail of Arrows
3) Triple the Elemental Shot damage bonus from 1 per level to 3 per level, with a +6 bonus if matching Genasi
Frenzied Berserker
Not bad, but rarely taken outside of Barbarian builds looking to retain purist bonuses due to the relatively steep cost of entry feat-wise, and the need to take Extended Rage feats to have good uptime on Frenzy. Adding bonus feats should alleviate this issue.
Suggestion:
1) Add bonus feats at Frenzied Berserker 5 and 10
Frost Mage
Looks decent on it's own, but heavily overshadowed by other caster PrC options. The damage bonus of Piercing Cold is simply too low to make the class attractive at its current value of 1% per level as it maxes out at a mere 10%.
Suggestion:
1) Increase the damage bonus to 3% per Frost Mage level so it caps out at 30%.
Harper Agent
Very solid already, but could be better with an additional Gift of the Gods at level 1.
Suggestion:
1) Add an additional Gift of the Gods at level 1.
Solid bonuses, but a wasted feat in Feint and no bonus feats.
Suggestion:
1) Add an additional feat at Invisible Blade 3 and 5
Lyric Thaumaturge
Very strong and flavorful bonuses, but Bards are already extremely feat-starved. This is even worse for caster bards who are seeking Automatic Quicken feats in addition to purist feats.
Suggestion:
1) Add bonus feats at Lyric Thaumaturge 3, 6 and 9.
Very interesting and flavorful class, but the bouses of getting a 2nd caster class at a low CL are not so strong as to warrant the loss of secondary class progression and a massive loss of feats outside of the edge case of exploiting the massive imbalance in runeword power for arcane casters to apply to a nature/divine caster.
Suggestion:
1) Change the bonus feat progression to 4, 8, 12, 16, 20, 24, 28, 32
Fairly nice bonuses, but the wasted feat needed to qualify is a huge cost.
Suggestion:
1) Add bonus feats at Sacred Fist 5 and 10
Similar to Sacred Fist, Stormlord has fairly nice bonuses, but wastes multiple feats to qualify.
Suggestion:
1) Add bonus feats at Stormlord 3, 6 and 9
Very solid already, but 10 levels with no bonus feats is a huge investment, and I do not think the Stormsongs themselves are so strong as to warrant no bonus feats (unlike Arcane Archer that gets Arrow of Death)
Suggestion:
1) Add bonus feats at Stormsinger 5 and 10
Tempest
Requirements are too harsh for the relatively modest bonuses.
Suggestion:
1) Improve Tempest defense to add +1 AB and +1 AC per Tempest class level when wielding two weapons and wearing light or no armor. This replaces the relatively modest +3 AC, +2 AB bonus at Tempest 5 with a far more attractive +5 AC, +5 AB
Weapon Master
Good bonuses at high cost, but still hard to justify taking more than 5 levels in this class as the Ruin feats are highly situational.
Suggestion:
1) Superior Weapon Focus bonus should increase by +1 for every Weapon Master Level above 5. This means a level 10 Weapon Master is looking at a +6 AB bonus.
2) Add bonus feats at Weapon Master 8 and 10.
Low Tier. These PrCs are generally only taken in very niche scenarios or as 1-2 level dips as they are very frontloaded. A significant rework could be considered in future, but it's out of the scope of this post.
Neverwinter Nine
Annointed Knight
Arcane Trickster
Assassin
Avenger
Black Flame Zealot
Champion of the Silver Flame
Daggerspell Mage
Daggerspell Shaper
Dark Lantern
Dervish
Dissonant Chord
Divine Champion
Divine Seeker
Doomguide
Dragon Warrior
Dragonslayer
Dread Commando
Dread Pirate
Dwarven Defender
Eldritch Disciple
Elemental Warrior
Elite Commando
Fist of the Forest
Forest Master
Ghost-Faced Killer
Guild Thief
Heartwarder
Hospitaler
Lion of Talisid
Master of Radiance
Mystic Knight
Nature's Warrior
Nightsong Enforcer
Nightsong Infiltrator
Shadowbane Stalker
Shadowdancer
Shining Blade
Skullclan Hunter
Swiftblade
Warpriest
Warrior of Darkness
Whirling Dervish
Wilderness Stalker