Nothing wrong with trading small swings. It's a very reliable way to do things. If you make 1.40 in Soymeal (which was very easy yesterday), that is $140 a contract (days pay for many people). 50K is enough to controll 40 contracts. Do the math and you find you just made $5600.00 in 20 minutes. That is a Months pay for many people.
So when I have a larger account, I see no real reason to change then ether. I will just add 7-10 as one of my set ups to watch.