LE Norman Osborne was a huge favorite of mine as is LE Goblin Princess.

From the really old figures IC R Black Panther, LE Irene Adler, U Spiral

Rather than stats, I'll focus on a specific power set that just doesn't appear with any regularity in modern figures:

Long-Range (8+) Barrier, for low cost on repeated clicks (so you can push to put up Barriers and not lose it)

Hello Pyro!

Some figures are now getting barrier via "special white power", but there is nothing like having a way to protect your team from the too typical 10+ range attacks (not to mention Outwit, Perplex, etc.)

True, but she got a little hosed by the rewording of the Morlock Team Ability.

Gone are the easy days of getting that attack value to a 12 by just moving up a few pieces. Now they have to be either Wildcards (not too many mutants like that) or fellow Morlocks (or that other keyword) of which there are like 6.

She looks like a train wreck, but I love V Psylocke from Xplosion. Top dial stealth, BCF, and enhancement, with decent numbers. Makes a great buddy for SI Dr. Strange or Dr. Doom.

Cosmic Justice LE Atom.

A great stealth shield, and a great Brilliant Tactician.

I used R Black Panther yesterday for a 150 pts/1 Action game. Was great.

a few that I still like using-

Clobberin Time V She-Hulk

Mutant Mayhem V Puck and R Domino

Cosmic Justice - V Cheetah

Fantastic Forces V Iron Fist is still great.

I have alot of old figs (pre-avengers) I still use that hold up very well, here's a small list of ones I seem to get good runs out of and still do well
-V Justice-Avengers TK (Sersi is horrible)
-R Kang (Push forever, all the Kangs aren't too bad)
-V Supergirl (Still a nice brick)
-U Superman (OR)(Seriously nice tie-up piece for JSA Keyword
-V Mockingbird, nasty tie-up piece
-V Shadowcat, X-Men tie-up
-V Bullseye (Always performs, can't wait to run him with Thunderbolts)
-U Wolverine (Sin) (Until I see the new one (hopefully yellow costume))
-U Nick Fury (Sin) (Re-released in Classics packs and such a good click)
-U Man of Steel (So much better than the non-Chase Superman figs now)
-REV Dr. Mid-Nite (great healer)
-LE Clark Kent (Don't have this one, but did, he looks and is efficient for his points).
-LE Dark Knight (Hes really good)
-V Echo (Really good for her points)
-V Psylocke (AW) solid stunning blow piece that won't go down easy)
-U Sentry (AW) Better than having a maybe on Charge or HSS, still good
-LE Jessica Drew (really nasty fig)
-V Icons Superman-Still a great, still a monster, and in the right hands, near untouchable.
-LE Ghost Widow-Great for the points still
-REV Lockjaw (Nasty piece still)
-V Hawkeye (FF) Really nasty in his day, still nasty, and can be Thunderbolt still
-V Ghost Rider (FF) great clix, great range
-U Wolverine (FF) Best Wolverine out there, can be near immortal with the right feats.
-LE Cain Marko-got a big boost from the new rules for new way Perplex works with replacement values
-V Spoiler (Still awesome for the points)
-V Obsidian (good JSA keyword range)
-V Havok, 44 points of X-Men awesome
-V Wonder Man-top heavy, but still great if you cant affor Namor
-V Domino (one of my personal favorites)
-U Longshot Still holds up well, still only up front X-Men prob
-V Spider-man (Ult) still one of the best Pounce pieces in the game
-U Phoenix (Ult) beastly with trick Shot or Elite Sniper
-U Superman (UN) Hes still just so good its scary, not as good as the new KC, but not bad by any means
-RE Destiny (really cheap prob, well worth it)

These are just SOME of the Golden Age figs that hold up well IMO or that I have played.

E Wildcat and Sandman (OR) can both still pull their weight.

Plastic Man from Hypertime. The whole REV is still amazing in today's game.

T. O. Morrow is still decent.

Depends on what you count as old

That Enchantress with Super Senses and Shape Change on her first click is still good

So is Rookie Psylock from AW

still may favorite Support piece.

Omni Man...dude is a BEAST!

DC Ares for me

i forgot about V silver samurai, and the qusinart U spiral, if you can get either one close enough they will mess some stuff up

Veteran Havok. At 44 points, you get: 8 range, energy explosion, 16DV+ Energy Shield/deflection, leadership, 10 AV, and a whopping 4 damage!