The only issue I take with this is that your latter set of 3 calcs only accounts for what they're doing to Raichu. Raichu is frail, but as a late game sweeper or Stall breaker is he ALWAYS going to be the one coming in? Say he's brought in to Ferro on a turn where it goes for Rocks, Leech Seed, or even Thunder Wave. Raichu gets to +3, and odds are in late game he's not getting hit again. Also, Looking at the calculator, your Ferro calc is off252 SpA Life Orb Starmie Psyshock vs. 0 HP / 0 Def Raichu: 230-270 (88.1 - 103.4%) -- guaranteed OHKO after Stealth Rock
Now that stinks. If Raichu's bulk is really that bad, I don't know how many setup opportunities you can grab.
With Lightning Rod, you could technically set up off Electric types like Rotom-W and choiced Magnezone, but nothing else, seeing as you only have one resistance/immunity and seriously crappy bulk.
252 SpA Magnezone Flash Cannon vs. 0 HP / 4 SpD Raichu: 78-93 (29.8 - 35.6%) <---- Magnezone 3HKOes after Life Orb recoil.
0 SpA Rotom-W Hydro Pump vs. 0 HP / 4 SpD Raichu: 148-175 (56.7 - 67%) -- guaranteed 2HKO <---good luck setting up now :I
0 Atk Ferrothorn Gyro Ball (150 BP) vs. 0 HP / 0 Def Raichu: 123-146 (47.1 - 55.9%) -- 78.5% chance to 2HKO <--what is this? Ferro getting the 2HKO on Raichu?
If freaking Ferrothorn and Rotom-W can cleanly 2HKO this thing, and Talon/Mega Lopunny/Serperior can safely revenge kill it...
...I'm sorry, I don't see much OU potential for it. Seems like our friend Raichu will go the way of Mega Houndoom.
0 Atk Ferrothorn Gyro Ball (128 BP) vs. 0 HP / 0 Def Raichu: 105-124 (40.2 - 47.5%) -- guaranteed 3HKO (Ferro's not 2HKOing w/out Hazards, and 53% with rocks)
+3 252 SpA Life Orb Raichu Focus Blast vs. 252 HP / 168 SpD Ferrothorn: 502-593 (142.6 - 168.4%) -- guaranteed OHKO
Raichu also can create some opportunities to set up the same way others can: threatening out. While his normal offenses are low, he's fast enough to pull some revenges, and his coverage is pretty sweet for an Electric type. Even assuming he can't set up, Raichu's not completely incapable of putting in work against defensive mons
252 SpA Life Orb Raichu Focus Blast vs. 0 HP / 0 SpD Magnezone: 291-343 (103.5 - 122%) -- guaranteed OHKO
252 SpA Life Orb Raichu Focus Blast vs. 248 HP / 192+ SpD Heatran: 192-229 (49.8 - 59.4%) -- 76.2% chance to 2HKO after Leftovers recovery
I think Raichu's problem is that he got thrown on a slate with several obviously better mons. I also think people are looking at him wrong because of the Tail Glow comparison to Manaphy. Manaphy's good bulk, defensive typing and ability mean he uses Tail Glow as a wallbreaker for mid game that avoids being worn out against Stall. Raichu's better speed and outright immunity to Paralysis, as well as stopping Volt Switch makes him better to function as a late game sweeper, when things that could exploit his set up turn are gone, though he still can do work against defensive builds.