So,
-Get vynil/leather/non-cloth seats in any color you plan to coordinate with.
-Match the door handle surround to this color/material. Then paint/sticker the window button/door pull plastic piece to this color.
-Match the bezel for the cluster as well as the plastic surround.
-color coordinated seat belts.
-Also you can do the radio/HVAC/hazard/defrost surround.
-If possible paint the vents for the A/C although that is close to impossible to pull off cleanly.
-You could always paint the back side and mount of your center rear view mirror.
-Also paint the HVAC knobs themselves and mask off the light area, unless you have EL faces in which that light doesn't matter.
-Floor neon in a matching color.
-HVAC faces in a complimentary color.
-Guage faces in a complimentary color.
-Maybe your radio face could match?
-Don't paint the center console or dash.
-maybe a new color dome light bulb, although it has to be useful, not just pretty.
-a knew shift knob isn't too bad if you drive stick.
-same with the e-brake.
-get color matched carpets, or carpet inserts, or that fake diamond steel bed liner look.
-unless new pedals are more functional than the factory ones, don't change them.
Remeber, nothing garish. Keep it mild on the colors, and match the seats as close as you can. They are the most prominent piece to the interior, so as long as you coordinate or accent off them, you should be ok.
Seth