Veterans and bling

How do you guys deal with "vetting" up space marines? Sure there are metal minis, looking cool, but I rather have plastic and more options. Feels like they can be built out of tactical squads and assault squads. They just need more "bling". Same goes for a command squad, they don't look as veteran as stermguard metal minis for instance.

Ive mostly seen people use the Dark angel upgrade sqrue robed guys for their vets.

Yah, I was going to mention the Dark Angels Veterans set too, as well as the Black Templars upgrade sprue. There is a little bit of "bling" on the armor in those sets as well as some bling like accessories. The robes are nice too. Admittedly there is allot of chapter specific iconography in those sets, but you could simply use it as personal heraldry for individual vets.
Here's some pics:

Another cheap and easy conversion is just putting scopes on all of their bolters and paint their helms white. It makes them stand out on the battlefield.

The upgrade sprues are pretty nifty. The jury is still out on the hoods though, I can't decide if they look nice or, well, too dark angels/black templars. I like the chains and the leafs on the metal figures, is there any simple way to get leafs etc for marines? I think I'd opt to get just the parts I need rather than the whole sprue, so a parts dealer would be needed. I don't think I'll branch out to Dark Angels anytime soon:)

Also what would be the best way to get a number of lightning claws, both left and right arms? I am as usual thinking of fun and odd ways of building armies:) For instance, putting a captain and a 5 man assault squad without jump packs in a razorback. Anyone done stuff like that before?

I really wish that GW could release more alt. model parts for us that handle greenstuff, well, not well at all.

I've been thinking of painting the helmets a different color, maybe purple (though the purple color I have from Valejo is several times worse to paint with than yellow, might have to pick up a GW pot or three of purples) and painting the captain up the same. That way I can get a captain and a command squad that fits nicely together.

I'm not sure which bitz stores are the best but three good looking ones I know of are:
the battlewagon bitz section of thewarstore.com
bitzbox.com
and the warhammer bitz section of thecombatcompany.com
combat company seems to have the best selection (or at least most of their stuff in in stock), but unless you're an aussie you'll have to pay overseas shipping.

For my Sternguard I have been using the copes like Capn said, and I have also added an ammo hopper from a storm bolter to their guns. I used the Iron Hands upgrade kit from GW on them as well to make them stick out a bit better. I tried painting one guys head white and hated the way it turned out - I'm not the best white painter.

Don't have "veterans" per-se in the CSM Codex, however I treat my Chosen Marines as veterans.
I go with the robed figures and bits from the DA and BT upgrade sprues, as well as loads of special weapons of course. Infiltrating melta CSMs screams veteran to me.