Miltank/Tauros pre-evolution...one that evolves to Miltank if female and Tauros if male. Makes sense.
Dunsparce evolution.
Tropius pre-evolution.
Pinsir evolution.
Absol pre-evolution.
Jynx evolution, it got the short straw with the Electabuzz/Magmar evolutions which I think is unfair.
Lapras pre-evolution.
Girafarig and Stantler evolutions and pre-evolutions.
Tangela pre-evolution, although I'm content with it as it is to be honest.
Farfetch'd evolution, I guess.
Torkoal should have a pre-evolution.
Seviper and Zangoose should both have pre-evolutions.
Corsola should have both a pre-evolution and an evolution.
Qwilfish needs an evolution.
Kangeskhan needs a pre-evolution, and 'M evolving into a Kangeskhan makes me believe that the guys at Gameshark were thinking about it when they made Red/Blue.
Spiritomb should have a pre-evolution.
Mawile and Sableye should have evolutions too, Mawile should be a Steel/Dark and Sableye keep Dark/Ghost or something.
Aereon - Flying type Eeveelution.
Toxeon - Poison type Eeveelution.
Arachneon - Bug type Eeveelution.
Terreon - Ground type Eeveelution.
Drageon (I guess) - Dragon type Eeveelution.
Steeleon - Steel type Eeveelution.
A ghost eeveelution too, I can't think of a name for it though.
And a complete revamp of Glaceon's art...Glaceon looks awful.
Edit:
No Marowak evolution, and I have reason.
"In Red & Blue, Marowak was originally supposed to evolve into Kangaskhan, but GameFreak removed it from the game files last minute. This was actually what created MissingNo, this is why MissingNo evolves into Kangaskhan. They had to replace the evolution files for Marowak > Kangaskhan somewhere, so they placed it in Cinnibar Island. This may also be why we don't/never will have a baby Kangaskhan, because under that little head of his in his mothers pouch, is a Cubone without its skull-mask. This may also be why "The skull on Cubone's head is that of its dead mother." - a dead Kangaskhan, Cubone runs around with a Kangaskhan's skull on its head, and while that Kangaskhan is still alive, it has no skull to put on its head."
Now, when I heard this for the first time my mind was blown, but it also kind of makes sense when you read that paragraph over a few times.
So theres your reason for not having a Marowak evolution, and also not to have a baby Kangaskhan, the reason being; there already is one, just not in the same evolution chain. :)
I retract my Kangaskhan statement after reading this, this makes everything much more interesting and clear.