I was going to post those three items as well, for the same reasons C:
Saint Ciel: Agape for the scissors, Little Lucie for the "Empty Eyes" and Lovely Lucie for the "Flirty Eyes", both of the Lucie eye mods can completely change the feel of the eyes, I usually use the one from Lovely Lucie (with hairstyles that cover the lashes) to make the Oisin/Cerynitian look "upset" or "annoyed", and Little Lucie's make most eyes look gloomy, I'm a head items junky so those three are in my "everyone should own" list XDDD I also think everyone should have a premium set of eyes and smiles~ it just gives your avatar more expressions C:
Everyone should have basic gold shop commons. Wool shirts, skinny jeans, basic skirts, leather belts and the like. You need a base to put all those shiny items on.
As for the shiny, I can't really recommend a single item that works for everyone. I guess I would say when you find that perfect item make it your own so that when people see you they say "Hey! it's that dude/chick. The one with the____."
I believe all Gaians require a towel. Partly because it has great practical value. You can wrap it around you for warmth; you can lie on it; you can sleep under it; use it to sail a miniraft down the slow heavy River Moth; wet it for use in hand-to-hand-combat; wrap it round your head to ward off noxious fumes or avoid the gaze of the Ravenous Bugblatter Beast of Traal, you can wave your towel in emergencies as a distress signal, and of course dry yourself off with it if it still seems to be clean enough
in general ( since anything specific i'd suggest would be wholly unpopular coughcoughdiaperedegghorns ) i would say to work your way up and buy a decent selection of wigs and eye / face mods that interest you. also, definitely stop at barton jewelers and stock up on small accessories, because little things like earrings, glasses and whatnot will give extra oomph to an otherwise dull avatar!
I am not comfortable dictating to (or being dictated to by) the masses, and I know my style is unusual these days; I avoid body mod poses and nearly always keep the same eyes and hair. I am also not a fan of lace, frills, or pink. sweatdrop
That said, there are a few items I am often surprised not to see on more avatars. The Woven Blazers, for example. They are cheap, simple, appear in some great colors, and have a very nice simple style. The Buttoned Down Boots fit in this category for me, too. They keep to the avatar's foot shape but don't look too blobby; they also have that nice detail of gold buttons. I think more females should use the Thistle Blouse; it has some great colors and can add subtle pizzaz to an outfit. Ume Blossom Hairpin is just about perfect, too; it boasts great color and placement, and it works for a ton of female avatars, although I can see why those with a male avatar would give it a miss.
Elf ears. I don't understand how anyone can go without a pair. They were the first thing I ever quested for and when I switched from being flesh coloured to the white body dye, I waited for the day admin to release white ones to match.