Whatever you decide to do, pick an amount to leave in the TSP so that WHEN you are not happy with all the fees and expenses that you will have (that you don't have with the TSP) you can come back to the TSP.
csh
Since my retirement 8 years ago, I explore this option just about every 6 months. Run through numbers, mull it over and end up not doing anything.
In my TDA and Schwab accounts I've managed my own investments for about 12+ years and have done quite well.
A person could use one of Schwab's zero commission ETF's. SCHD (Dividend Equity ETF) the fee is 0.06% and the dividend yield is 2.90%. Assuming diversification on a 1MM TSP, putting 10% into SCHD the expenses would be about $60/year and the dividend would be about $2,900. The average dividend on a portfolio of 10 ETFs, could be about 1.4%. On a 1MM account that is $14,000 with an expense average of about $1,000.
Keeping this thread moving in the on topic question, doesn't it seem reasonable to consider doing this?