I generally like summer more than winter because you can do much more outside (like swimming, grilling evenings etc.) and there's much more sunlight to enjoy. Where I live, it's getting dark at 5pm in winter and 11pm in summer (with DST) - of course I prefer the latter. Plus you can simply go outside without slapping on heavy gear and it doesn't get all wet and dirty when you go back in unlike when there's snow. And I hate icy roads, such a waste of time.
But of course it shouldn't get too hot. My preferred sleeping temperature is around 15°C/59°F and everything above 20°C/68°F is too warm for my room. Last summer there were some weeks during which I couldn't get my room temperature below 27°C/81°F and you have no idea how hard it was to fall asleep. Needless to say I sweated a lot while sleeping (eww) and therefore had to change stuff very often.
Since around mid April, we've been having very nice weather here, with daytime temperatures of 20-27°C/68-81°F and at night 10-15°C/50-59°F, that's warm enough to go swimming etc. outside but still cool enough to sleep. For me it could stay that way all year!