I dunno i like messsing with the settings. I can calbrate my ht in about 5 min with just a disk and an spl meter not a huge ordeal at all to me anyways. If its your hobbie its something you should enjoy doing. Anyways don't want to start a fight but there are set backs in everything. I don't see any real reason for constant mantaince on a ht. Its a lot easier than a car and once levels are set and phase your good and shouldn't have to touch it. Car is much more complecated to set up.
Anyways as for you your car my suggestion you have enough power so i would say ported or bandpass. Bandpass will probably be the loudest. Won't sound the best but will be the loudest. Youll probably need a subsonic filter as well so you don't blow the speakers. Or you could jsut open the trunk and all the doors when you want to hear it outside.