@walking.dude "Red Dredge" is essentially what people used to play in Vintage a long time ago (it wasn't Red spells at the time because the primary discard outlets were Blue). People used to play Careful Study, Breakthrough, Cephalid Coliseum, and Putrid Imp. By the time Bloodghast was printed, some Dredge lists (a minority) still used those cards instead of Serum Powder. Evolution of Dredge over time led to Serum Powder being the dominant version of Dredge. I have doubts that going back to something similar to that old technology would bare much fruit.
@Smmenen I'm not terribly convinced that Flash would have a good matchup against Workshops if it were unrestricted. Phyrexian Revoker and Walking Ballista are both creatures that were not printed before Flash was restricted and both of them can stop the Reveillark kill. I have a hard time imagining that Disciple of the Vault is good enough to avoid this weakness (too much deck space), but maybe? Is there perhaps other viable Flash kills enabled by newer printings that haven't been explored?
@jhport12 I'll give a couple examples of some once dominant decks that have fallen off due to easily identifiable (in my opinion) recent printings.
Bob-Jace have a very notable series of printings that led to the decline of the once dominant deck. As I know it, it's generally agreed that the printing of Delver of Secrets and then Young Pyromancer pushed Bob almost completely out of the format and massively reduced the once supreme power of Jace, the Mind Sculptor.
I'd make a strong case that "the rise of creatures" in general has greatly reduced the power of Planeswalkers for a very straightforward reason. Jace isn't a very good Jayemdae Tome when the opponent has a board position that ensures his death next turn. Bob was pushed out because the tempo-oriented Delver decks could put on some quick damage with Delver and had finishing power with Lightning Bolt; it was too much damage for Bob to be a reliable draw engine without seriously risking your own death.
I'd also say Tinker has some notable printings that have led to its decline from a once dominant deck. Grafdigger's Cage was the first printing that directly hated on Tinker that saw wide play because of its useful Graveyard hate, and Containment Priest now also falls into that category.
More so than the hate, though, I'd say that Tinker suffered a lot from the printing of Flusterstorm as an effectively uncounterable counterspell that stuffs Tinker. Control decks used to hinge their whole game plan on maneuvering the game such that they could cast a Tinker and win the counter battle over it, thus securing the game. Flusterstorm aimed at a Tinker essentially ensures that Tinker doesn't resolve and so it became a much, much less reliable finisher. Then, of course, there's the much more obvious printing in Dack Fayden that heavily punishes Blightsteel Colossus. The printing of Monastery Mentor hit Tinker with from two different directions at once:
Mentor led to the "rise of White", which of course brought Plow back into the format as a main deck card, both because Mentor decks are White and can run Plow themselves, but also because Plow hits Mentor. I.e. more Plow = Blightsteel Colossus is unhappy.
Mentor basically just slotted right into the spot formerly occupied by Tinker as the de facto finisher of Control decks. Why run Tinker when it has so many weaknesses, when you could just run Mentor instead, without any of those weaknesses, and win about as quickly?
Well that was a longer post than intended. Fun though. There's plenty of examples of cards that used to be highly dominating, but have fallen off lately. In no particular order, Mental Misstep, Flusterstorm, the Delve spells, Dack Fayden, Young Pyromancer, and Mentor are probably the biggest 'offenders' for reasons why formerly dominant cards are no longer played nearly as much.
@rikter You can probably cut a Golgari Thug or two if you're running the full package. As for the DR target, I would be uncomfortable without a way to lock up the game. FKZ is the most standard choice and that's what I run. I've seen people use Iona, which I've never tried, but I'd like to, to see how it plays, so that's probably fine too. Going without either one seems risky, though. Other DR targets are luxury secondary targets for niche situations. They're fine to have if you've got the room, but it's okay to run without them.
I ran with FKZ as my only Dread Return target for quite a long time and it works out fine. Dread Return on Golgari Grave-Troll is decent enough if you can't manage to find FKZ or you exiled him with Serum Powder. I'd say at least 90% of the time, the game is locked up by the time you cast Dread Return anyway because of Cabal Therapy. Right now I run Elesh Norn alongside FKZ as a luxury DR target primarily because it's good against Shops if my Bridges get destroyed.