Wow! This new thread has been a surprice and I'm happy that we are talking about that, but please don't be too "aggressive" in the selection of cards that you want to remove, because I've seen a general underestimation of cards that instead may have their good use, especially in other formats than Vintage. Power is not the only goal, but also the fun that a card may provide.
What follows is my personal opinion in detail:
Cloned cards - I also agree about removing the ones (as Moor Fiend or Ravages of War) that do not offer any benefit in a number greater than 4, while I wouldn't remove some useful ones as the "Pump Knights" or Fyndhorn Elves (clones of Llanowar Elves) because there are some decks that can use 8 of them succesfully.
Vanilla creatures - Not all vanilla cards are ugly: Woolly Thoctar is a vanilla card and is great

But also older ones as Fire/Earth/ Water Elemental or Grizzly Bears are vanilla cards and are more than decent. So please remove ONLY the ones from the Legends and Dark that have a bad ratio among power & casting cost. Please, don't remove Jasmine Boreal and Sir Shandlar of Eberyn.
Unlimited Set - Even if I would be very happy to see the Laces and Unlimited lucky charms disabled (they are not bad but the new ones are much better), remember that changing cards from Unlimited set will affect Shandlar too and thus they can't be removed: in fact, as far as I remember,
Shandlar and the Duel share the same art and CSV (cards.dat), which actively influences cards behavior. Also, Unlimited set has a valued as 99% completed set in sealed game. At this purpose, Wards can have a value for weird combos and as Sideboard Cards, while Banding may be strong in such game modes with a low ratio of direct anti-creature spells.
Legends & Dark - I know that those sets did include a lot of junk, but please don't be too radical in removing them all. Eg, I don't see any reason to remove the mana batteries, since they can be useful in Sealed Deck games. There is much worst to start from.
Astral set - For reasons that I've explained elsewere, I would remove all of them except Aswan Jaguar and Fairy Dragon. But changing them would affect Shandlar too.
Ante Cards - Ante is part of the game, there are ante modalities and so those cards can be used in sealed deck game and may be very powerful (especially Contract from Below). IMHO, they should NOT be removed.
Bouncelands - I dislike them too, because they are very slow and because the AI makes a terrible use of them.
If you really want a solid list of cards to remove, let's start from here: they are already
34 free slots, so there is no reason to start "killing" other cards.
8th EditionCoastal Hornclaw (it is the only card from that set which is really ugly!!)
Unlimited Laces (just disabled)
Manalink 2.0 the five "voice of ..." Angels. With Voice of All, they are all made obsolete. Even if they have other minor advantageas, as a less-confusing use for AI, lower rarity in sealed deck and a slighty cheaper casting cost, those advantage do not compensate the space that they take.
Legends.557 Aisling Leprechaun - can't find any application, there are better pixies
.577 Barktooth Warbeard - vanilla and/or ugly creature
.669 Hell Swarm - surpassed by Marsh Gas
.667 Headless Horseman - vanilla and/or ugly creature
.676 Hunding Gjornersen - vanilla and/or ugly creature
.689 Jedit Ojanen - vanilla and/or ugly creature
.695 Kasimir the Lone Wolf - vanilla and/or ugly creature
.708 Lady Orca - vanilla and/or ugly creature
.727 Mold Demon - vanilla and/or ugly creature
.748 Princess Lucrezia - vanilla and/or ugly creature
.744 Planar Gate - too mana-expensive for being used
.757 Raging Bull - vanilla and/or ugly creature
.759 Ramirez DePietro - vanilla and/or ugly creature
.776 Riven Turnbull - vanilla and/or ugly creature
.790 Sivitri Scarzam - vanilla and/or ugly creature
.388 Word of Binding - just ugly
.721 Mana Matrix - too mana-expensive for being used
.620 Elder Land Wurm - vanilla and/or ugly creature, personally would like to see it "upgraded" to Alabaster Dragon or another nice white dragon.
.621 Elder Spawn - vanilla and/or ugly creature
Dark.308 Coal Golem - useless mana source
.314 Erosion - out of flavor for blue, useless
.937 Goblin Rock Sled - ugly even as sidebard card vs. red
.335 Hidden Path - self-suicide card
.343 Mana Clash - useless and ugly
.345 Martyr's Cry - ugly and extremely limited
.948 Squire - made obsolete by tons of better cards, useless even in sealed deck
.950 Tivadar's Crusade - too specific and useless, since we don't have a sideboard.
Also, even if it is not so bad by itslef, I would prefer to see Angry Mob upgraded to Crusading Knight.
Even more, I wouldn't remove Righteous Avengers because it may be a nice sideboard card in Sealed Deck and would never remove the ugly (I know) Akron Legionnaire for affective values: when I was a kid, I did a deck with Urza's Land, Angelic Voices and only Artifact creatures to use the Legionaire and I love to have it here on the PC

Pleaseeeeeeeee
