I'm pretty sick of FR-bashing myself. I'd say that FR products probably contain options for feats, PrCs, and spells that are mechanically superior to core options, but these are still inferior to the splatbook options, most options contained in third-party products, and certainly most options in OA/Rokugan products.
Here's my list of problematic FR options:
-Spell Power: This one isn't necessarily even overpowered, depending on how easily acquired save bonuses are IYC. If you do consider it overpowered, the key is to limit spell power progression for the shadow adept and the archmage (the red wizard and hierophant both pay a heavy enough price for the ability), or to disallow spell power from different sources from stacking.
-Spellfire: ONLY problematic at low levels. At 5th level or higher, the ability to inflict 18d6 damage on one creature with a ranged touch attack subject both to spell resistance and a Reflex save is actually not particularly great, at least if you consider the fact that this is only usable once at a time, costs 18 levels worth of spell slots, and requires an 18 Con to employ, and a high Dex to aim properly. Spellfire really only creates issues when that once-per-day blast can obliterate the DM's favored BBEG. Besides, it's subject to DM approval for a reason.
-Spelldancer (funny pattern we're building here, no?): This is just poorly written. The infinite feedback loop just needs to be eliminated, which is possible if you place a simple limit on the number of rounds of spelldancing possible per day.
-Kiss of the vampire: Just raise this spell a level.
-Incanatrix: The problem with this class isn't the class itself; it's the interaction of a stackable Empower Spell feat and the Improved Metamagic ability (something which comes up for epic-level characters, BTW). My solution is to forbid Empower from stacking with itself unless the feat is taken multiple times.
What else d'you have problems with?