I think I play as safe as the position allows me to. In general I agree with piggy, I also consider myself an agresssive player, by which I mean if you have the tiniest advantage you need to be agressive in some way in order to convert it. Stack advantage? Attack enemy stacks/eliminate them. Income advantage, trade stacks/bonuses. Positional advantage, trade it for one of the previous 2 etc. etc.
http://warlight.net/MultiPlayer?GameID=5330318An example of an early income edge that was a really slight advantage since we did not border immediately, during the game I felt like it was an almost perfect mix of agression and safety. Also your game against Summer does not tell us much about that safe style of picking you're talking about, you leave the decision up to your opponent if he counters you or not. Overall, if with your picks you do not see any alternate picks that'd put you in an instantly much worse position, you should be fine with decent play.