Churning is one of the most well-established securities violations. You likely have claims through FINRA arbitration (mandatory for most brokerage disputes):
Key metrics: Courts and FINRA panels look at (1) turnover ratio (number of times the portfolio was turned over — above 6x annually is presumptive churning), (2) cost-to-equity ratio (annualized costs as a percentage of account equity — above 20% is excessive), and (3) whether trades were suitable for your stated objectives.
For a conservative retirement account with 200+ trades, your case is strong. The advisor also likely violated their suitability obligations (FINRA Rule 2111) and fiduciary duty if they had discretion over the account.
Damages: The typical recovery is the difference between your actual account performance and what a properly managed conservative portfolio would have earned (a "well-managed account" analysis). Plus commissions generated by excessive trading.
FINRA arbitration is faster than court (typically 12-16 months). Securities attorneys usually work on contingency (25-33%). Your brokerage firm is jointly liable for the advisor's misconduct under respondeat superior.