your new bike is beautiful, not overkill by any means. Im sure you will get every penny out of it.

1.) I would recommend taking off the near useless reflectors and replacing them with a front light and a rear blinky as suggested (even for day use). maybe even a helmet light if your riding at night.

2) mtb pedals and shoes are fine if your ok w/them. when these need replacing buy some speedplay.

3) as far as clothing I like bibs that come up high in front. My jersey's all have rear pockets and at least a partial zipper. I dont buy very flashy, multi colored, logo splattered, kit. I stay with black bibs and maybe 3 colors (one being black) shirts. this is what I found comfortable and not too goofy looking, so long as your comfortable and people arent cracking up when you ride past, then your wardrobe is fine.

enjoy. and wear your helmet.