I'm like you, it can take me hours to choose papers for a page-so the evenings leading up to a crop I sit and make page kits with several options for pps and cs. If I know of embellies that I know for sure I want to try I add those to the kits, but I usually avoid bringing my embellies and do that latter after the crop.
I always overestimate how much work I can get done in a day just in case. I try to plan designs out in advance so I can do any die cutting in advance and can avoid hauling my cricut, but my big shot usually comes along anyway.
I bring my tool tote with me, and I usually end up hauling most of my distress inks along to use on the pps. I also bring any shape cutters that I use a lot (mainly circles). And then of course extra adhesive, that way any shopping I do is for fun stuff and not for adhesive!