you can use QuickDetailer type sprays with a soft plush microfiber towel to remove. next time you wash the car put some wax or polymer sealant on the front bumper and side mirrors (if you're lazy to wax the entire car). that alone will make your quick detailer session go a lot faster.
i too recommend you take bug guts off as soon as you can so that it does not stain the finish.
if you're going to wash it, i use Wizard's BugRelease spray after the initial wetdown. let stand 2min and just wash with your mitt.