Been a while since I took part in CAP
Anyways, I would like to expand a bit on Revenankh's support movepool and give it Will-o-Wisp. If I can recall, one argument used against it was because it would be too much like Dusknoir. However, since Dusknoir has been trashed nowadays we shouldn't care about it much anymore
With Will-o-Wisp, Arghonaut can be seriously crippled as it uses physical attacks to deal damage, and it becomes less effective at taking hits. Fidgit also doesn't like being burned all that much, given that its only recovery move is Wish. Furthermore, Will-o-Wisp can deter Calm Mind Jirachi from swapping in and wrecks Metagross, Gyarados and Salamence to an extent. You can also use it in conjunction with Taunt to beat up slower arghonaut and Gyarados. With four moves, I highly doubt it'd become broken. Also, for flavor reasons, all the other ghosts bar frosslass gets it :). And if you think WoW does not fit just because he looks flammable...well honestly, explain Fire Blast Weezing or Cutless Zangoose, or Ice Punch Kitsunoh.
EDIT: I'd also like Shadow Claw for the power boost and Zen Headbutt for Fidgit/Arghonaut.
EDIT2: Will-O-Wisp also makes Kitsunoh cry
EDIT3:
Okay now that I've thought about it, I recommend changing Rev's base stats to:
100/100/90/65/120/65 +10 HP -5 Atk +20 SDef. BST = 540
PSweep: 121 (Rank 4: Above Average)
PTank: 157 (Rank 6: Very Good)
SSweep: 88 (Rank 3: Below Average)
STank: 203 (Rank 8: Fantastic)
ODB: -13.46 (Biased towards Defense)
PSB: -1.9 (Slightly biased towards Special)
Overall Rating: 311 (Very Good)
Before you go anywhere, some of you think it might be crazy to sharply increase its Special Defense ad add in a bit to HP on something already tanky as Revenankh. Looking back at the Rev analysis however, Fidgit, Kit and Argho aren't its only problems. Rev has problems taking several special hits and I wish to fix this. The prime target for this base stat change is Cyclohm, and in consequence, Draco Meteor Salamence. Cyclo's Life Orb Draco Meteor, for instance, does 50%-59% to the 90/100 Rev, and Thunderbolt deals 34%-40%. This simply means that Rev can be 2HKOed by Bolt + Meteor in sandstorm, and 3HKOed by Thunderbolt + Thunderbolt + (either another TBolt or Meteor) in Sandstorm's absence. With massive physical defense, Cyclo can swap in quite easily too.
With the sharp boost in HP/SDef, Draco Meteor now does 50% maximum to Revenankh, and Thunderbolt deals 34% maximum (in other words, the minimums in the current stat spread is now the maximums in this stat spread). This means that
1) When sandstorm is not around, Timid Cyclohm has a 10.361% chance of KOing Revenankh with Thunderbolt + Thunderbolt + Draco Meteor
2) When sandstorm is around, Cyclohm can not KO Rev with Thunderbolt + Draco Meteor.
Salamence's Draco Meteor does around the same to Rev as Cyclo's, and if you get two Bulk Ups he's not going to bust Rev up with Outrage
Other calcs (against new Rev, max/max careful):
Min SAtk Togekiss Air Slash: 30-36%
This will at least give Rev a fighting chance, with Air Slash being a 4HKO instead of a 3HKO. Togekiss will probably win anyways due to flinch
Max SAtk Jirachi's Psychic: 39%-46%
256 SAtk Jirachi's Psychic: 34%-40%
No longer has that shot to 2HKOing barring SDef drop from Psychic on the first calc. Second calc means that a SDef drop from Psychic won't kill Rev.
Starmie also only has a 14.045% chance of 3HKOing new Rev with Hydro Pump, allowing it to spinblock better. This not only allows Rev to defeat it with ease, but to also set up on it which it may have problems doing so with the old spread.
To compensate for the bulk increase, I dropped the Attack stat by 5 points. This should not hurt Rev that much, however.
Bulk Up Hammer Arm (min Atk) vs Cyclohm (min HP/Def): 40%-46 (this is assuming Cyclo switches into Rev, unless the analysis lies)
If Cyclo tries to Slack off stall this, you can easily snag in another Bulk Up. If sandstorm is not active, you are free to Hammer Arm it for a bit till Leftovers heals enough for you. Under sandstorm, just grab a second bulk up and beat up Cyclo with Hammer Arm + Shadow Sneak (Life Orb + sandstorm will wear him down very quickly).
Is it too much?
It shouldn't be too much IMO. Rev still falls to Kit, Arghy, Fidgit with this base stat arrangement alone. He is also still stopped by his usual counters, but no longer falls prey Cyclo and has a better fighting chance against other special attackers. Then again, my definition of "too much" may differ greatly from yours. Chances are he doesn't need this stat boost, but it would certainly help him a bit. If you don't like it, feel free to ignore it.