Buying more, but smaller stakes

Recently I've been reading Tharp's Trade Your Way to Financial Freedom and thinking about position sizing again.  I had decided that I had too many stocks and was going to have fewer, bigger stakes.  That might have been okay, except that it exposes you to a larger capital risk on one stock.  

So now, I'm writing down my stock purchases with a sell rule for the up and downside.

For example yesterday morning I bought some PAY at $37.98  My loss limit would be at the 50dma of $34.46, which is about 9%.  1R of my current portfolio is $75, so 75/0.09 is $822.  (Losing 9% of 822 is $75 lost.)  Divide that by the shareprice and I bought 20 shares, just to have a round number.

This can change the amount of your position size, depending on how much risk there is in the stock.  For example, other recent buys at the end of last week were CBG and KPN.  CBG had a breakout to a new high.  I bought it with a loss limit of 8.5% (close below 50dma) and got $860 worth.  KPN had a high volume upday and I bought it at 14.76 with a sell rule of 14, or 5% and bought $1460.  If you look at both loss limits, it's for the same dollar amount, but CBG is risking a larger percent, so it's for less total stake of my portfolio.