Another really big factor is that because I cut 1/2 the position when trading 200 lots, if I only have 100 and I should have taken a profit, what do I do? I usually hold the position until/if it breaks even. And this really messes things up.
Always a % of what is at risk. You could be trading futures with 20% down , i.e margin amount or stocks, 100% margin and the only thing that is common is the risk needs to be dealt with according to your $ risk in each trade.
