i'm playing the stress-free way myself (when i remember to play at all), but i will say this: i didn't bother at all with leaderboards for a couple of times, only spinning the wheel sometimes because i like spinning wheels, and breeding/evolving at my normal slow pace. so because i did so poorly in the rankings those times, i got put into a much less-motivated group. which was awesome, because this last one i actually liked the final prize, so it wasn't all that hard to win it against the group i was in. (i did boost a couple times when i had breed/hatches/evolves/spins all due at once, but i thought the final dragon was worth the 30 gold or whatever.)
not even attempting bingo.