Swampert is only good as a Swift Swim attacker; going defensive wastes away that niche. Besides, there are defensive Water (and Ground) Pokemon that do Swampert's job better, such as Slowbro, Therian Landorus, Gliscor, and even Empoleon and Garchomp:
Slowbro:
-Scald
-Psyshock/Foul Play/Fire Blast/Ice Beam
-Thunder Wave/Toxic
-Slack Off
Nature: Bold
EVs: 252 HP/232 Def/24 SDef
Item: Leftovers/Rocky Helmet
Ability: Regenerator
or
-Calm Mind
-Scald
-Psyshock/Iron Defense
-Slack Off
Nature: Bold
EVs: 252 HP/148 Def/108 SDef
Item: Slowbronite
Ability: Regenerator
Therian Landorus:
-Stealth Rock
-Earthquake
-U-turn
-Stone Edge/Knock Off/Rock Slide
Nature: Impish
EVs: 252 HP/240 Def/8 SDef/8 Spe
Item: Leftovers/Rocky Helmet
Gliscor:
-Stealth Rock
-Earthquake
-Acrobatics/U-turn/Toxic/Taunt
-Fling/Knock Off/Toxic
Nature: Impish
EVs: 252 HP/36 Def/224 Spe or 252 HP/184 Def/72 Spe
Item: Toxic Orb
Ability: Poison Heal
Empoleon:
-Scald
-Roar
-Toxic/Stealth Rock
-Defog/Stealth Rock
Nature: Calm
EVs: 248 HP/8 Def/252 SDef
Item: Leftovers
Ability: Torrent
Garchomp:
-Stealth Rock
-Dragon Tail
-Earthquake/Toxic
-Fire Blast/Toxic
Nature: Impish
EVs: 252 HP/164 Def/92 Spe
Item: Rocky Helmet
Ability: Rough Skin
Noivern faces heavy competition from other Dragon Pokemon such as Dragalge, Lati@s and even Hydreigon, mainly because of its lack of power compared to them. Dragalge also has the nice bonus of hitting Fairy Pokemon hard with its Poison STAB. Draco Meteor chunks most walls hard; Boomburst is redundant coverage with it. Besides, Noivern's offensive move pool is pretty decent and you're not really making use of that:
-Hurricane
-Draco Meteor
-Flamethrower/Focus Blast
-U-turn/Roost
Nature: Timid
EVs: 4 Def/252 SAtk/252 Spe
Item: Life Orb
Ability: Infiltrator
As I already mentioned, the above Dragons may be a better fit than Noivern:
Dragalge:
-Toxic Spikes
-Sludge Wave
-Draco Meteor
-Focus Blast/Hidden Power (Fire)
Nature: Modest
EVs: 228 HP/252 SAtk/28 Spe
Item: Draco Plate/Dragon Fang/Black Sludge
Ability: Adaptability
or
-Toxic Spikes
-Sludge Wave
-Draco Meteor/Dragon Tail
-Scald
Nature: Calm
EVs: 252 HP/228 SDef/28 Spe
Item: Black Sludge
Ability: Adaptability
Latias:
-Draco Meteor
-Psyshock/Hidden Power (Fire)
-Defog
-Healing Wish
Nature: Timid
EVs: 72 HP/184 SAtk/252 Spe
Item: Life Orb
Latios:
-Draco Meteor
-Psyshock
-Surf/Hidden Power (Fire)/Earthquake
-Defog/Roost
Nature: Timid/Hasty
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb
or
-Draco Meteor
-Psyshock
-Tailwind/Defog/Hidden Power (Fire)/Surf
-Trick
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Choice Scarf
Hydreigon:
-Draco Meteor
-Dark Pulse
-Flash Cannon/Fire Blast
-Superpower/Earth Power
Nature: Mild/Modest
EVs: 4 Atk/252 SAtk/252 Spe
Item: Life Orb
or
-Draco Meteor
-Dark Pulse
-Earth Power
-U-turn
Nature: Modest/Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Choice Scarf
Umbreon is outclassed by Mandibuzz as a defensive Dark Pokemon because it provides Defog support. It's also outclassed by Mega Sableye, thanks to it not giving a crap about most status moves thanks to Magic Bounce. Sylveon and Clefable also do the Wish role better because both have better defensive typings to take advantage of. Mega Altaria also has excellent utility options to use:
Mandibuzz:
-Foul Play
-Roost
-Taunt/Whirlwind
-Knock Off/Defog/Toxic
Nature: Impish/Bold
EVs: 248 HP/136 Def/108 SDef/16 Spe
Item: Leftovers
Ability: Overcoat
Mega Sableye:
-Calm Mind
-Shadow Ball/Dark Pulse/Snarl
-Will-o-Wisp
-Recover
Nature: Bold
EVs: 252 HP/252 Def/4 SDef
Item: Sablenite
Ability: Prankster
Sylveon:
-Wish
-Protect
-Hyper Voice
-Heal Bell/Toxic
Nature: Bold
EVs: 252 HP/220 Def/36 SDef
Item: Leftovers
Ability: Pixilate
Clefable:
-Calm Mind
-Moonblast
-Wish/Moonlight
-Protect/Heal Bell/Aromatherapy
Nature: Bold
EVs: 248 HP/252 Def/8 SDef
Item: Leftovers
Ability: Unaware
or
-Moonblast
-Heal Bell/Aromatherapy/Thunder Wave
-Wish/Moonlight
-Protect/Stealth Rock
Nature: Bold
EVs: 248 HP/252 Def/8 SDef
Item: Leftovers
Ability: Unaware
Mega Altaria:
-Dragon Dance
-Return
-Earthquake
-Roost/Fire Blast
Nature: Adamant
EVs: 252 Atk/4 Def/252 Spe
Item: Altarianite
Ability: Natural Cure
or
-Hyper Voice
-Fire Blast
-Heal Bell/Earthquake
-Roost
Nature: Modest
EVs: 4 Def/252 SAtk/252 Spe
Item: Altarianite
or
-Dragon Dance
-Return
-Earthquake/Substitute/Heal Bell
-Roost
Nature: Impish
EVs: 248 HP/136 Def/96 SDef/28 Spe
Item: Altarianite
or
-Return/Hyper Voice
-Earthquake/Fire Blast/Roar/Perish Song
-Heal Bell
-Roost
Nature: Impish/Bold/Relaxed
EVs: 248 HP/104 Def/156 SDef
Item: Altarianite
BellyJet Azumarill needs enough Speed to outspeed uninvested base Speed 70s like Skarmory. Superpower is detrimental on Belly Drum sets, as it lowers Azumarill's Defense and detracts part of Azumarill's maximized Attack after each use, meaning that Azumarill may still be forced to switch later on. Knock Off is also the preferred option over that, as it still severely damages Ferrothorn and Amoonguss after a Belly Drum boost:
+6 252+ Atk Huge Power Azumarill Knock Off (97.5 BP) vs. 252 HP / 136+ Def Amoonguss: 524-617 (121.2 - 142.8%) -- guaranteed OHKO
+6 252+ Atk Huge Power Azumarill Knock Off (97.5 BP) vs. 252 HP / 88+ Def Ferrothorn: 344-405 (97.7 - 115%) -- 87.5% chance to OHKO
Tl;dr:
-Belly Drum
-Aqua Jet
-Play Rough
-Knock Off
Nature: Adamant
EVs: 92 HP/252 Atk/164 Spe
Item: Sitrus Berry
Ability: Huge Power
IMO, there are better alternatives to your Talonflame set. Despite its middling stats outside of Speed, it can perform a pretty wide variety of roles, ranging from a standard revenge killer (with Choice Band or Swords Dance) to even a specially defensive variant. For sweeper sets, don't put the last 4 EVs into HP, as it makes Talonflame's HP even, meaning that it gets KOed upon 2 switch-ins to Stealth Rock:
-Swords Dance
-Flare Blitz
-Brave Bird/Acrobatics
-Roost
Nature: Jolly
EVs: 252 Atk/4 Def/252 Spe
Item: Sharp Beak/Sky Plate/none
Ability: Gale Wings
or
-Swords Dance
-Brave Bird/Acrobatics
-Will-o-Wisp/Taunt
-Roost
Nature: Adamant
EVs: 248 HP/252 Atk/8 Spe
Item: Leftovers/none
Ability: Gale Wings
or
-Acrobatics
-Roost
-Bulk Up/Taunt
-Will-o-Wisp/Taunt
Nature: Careful
EVs: 248 HP/252 SDef/8 Spe
Item: none
Ability: Gale Wings
or
-Flare Blitz
-Brave Bird
-U-turn
-Steel Wing/Tailwind
Nature: Adamant/Jolly
EVs: 252 Atk/4 Def/252 Spe
Item: Choice Band
Ability: Gale Wings
In the last slot, a Grass Pokemon can work for the team, as it pairs well with Talonflame and the Water Pokemon of your choice. Examples are Ferrothorn and Serperior:
Ferrothorn:
-Stealth Rock/Spikes
-Leech Seed
-Gyro Ball/Thunder Wave
-Power Whip/Protect
Nature: Relaxed
EVs: 252 HP/88 Def/168 SDef
Item: Leftovers/Shed Shell
Ability: Iron Barbs
Serperior:
-Leaf Storm
-Hidden Power (Fire)
-Dragon Pulse
-Giga Drain/Taunt/Knock Off
Nature: Timid
EVs: 4 Def/252 SAtk/252 Spe
Item: Life Orb
Ability: Contrary
or
-Substitute
-Leech Seed
-Leaf Storm
-Hidden Power (Fire)
Nature: Timid
EVs: 4 Def/252 SAtk/252 Spe
Item: Leftovers
Ability: Contrary
If you didn't opt for any of the Mega Evolutions I suggested earlier, Mega Sceptile would be ideal in the last slot:
-Substitute
-Giga Drain
-Dragon Pulse
-Focus Blast
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Sceptilite
Ability: Overgrow
or
-Leaf Storm
-Dragon Pulse
-Earthquake/Protect
-Hidden Power (Fire)/Focus Blast
Nature: Naive/Timid
EVs: 4 Atk/252 SAtk/252 Spe
Item: Sceptilite
Ability: Overgrow
