this is all a little much if you're just starting out and on a budget. i still ride my CAAD with cages/toe clips/running shoes. i only have one jersey which i never wear.

the only stuff i consider "essentials" are a helmet, pump (since only bike shops will have presta), and my little ziploc bag which contains a spare tube, multi-tool (which has tire levers). oh, and i ride at night a decent amount so lights, front and rear. i keep this stuff in the spare pockets of my camelbak.

i HAVE some of the other stuff... a spoke wrench, glasses, gloves, bike computer, etc. but i'd hardly call them essentials.

i'd say as long as you're safe (helmet, hydration) and ready in case of a problem (pump/spare tube, or at least a cell phone for a pickup), worry about the rest later.