4 pics per month?
Maybe try and go through the dex?
Skipping every mon you already drew...
Starting with Bulbasaur :P

I, uh, I'm not sure if she can handle doing a Magnemite.

Hobbies.

How about "Legendaries"? idk

Oh! You could try Mega Evolutions!

I like that

Mega evo's or legendaries would both be really cool themes

Mythical pokemon?

Go and be orginal what about Fossil Pokemons?
you know pokemons like Aurorus or Aerodactyl

Gym Leader or Elite 4 Pokemon -- the main pokémon for each gym leader and you can pick a way to categorize:
• Logical order by region
• Each month pick a type, then highlight a subset of leaders of that type from the different regions

Addons:
• Rendition of respective gym badge.
• Performing a move that belongs to the pokémon in-game.

Hmmmm, how about Voted Types! people vote and the top maybe 5 types are the main focus for that month.
For example say steel, water, bug, dark, and dragon are the winners so for the whole month it will be pics of pokemon of just those types and the best part it can be mixed up every month

I like that :3

how about some beta Pokemon?

Ooh! What about Eveelution Fusions? I would love to see you do a Espeon Umbreon Fusion, your art style would just...bring it to life!

You can make something more "basic" and do like feline, canine and such as well!

Pokemon meets Digimon? Take a Pokemon, find a similar looking Digimon, and put em together.

For example: blackwargreymon & aggron

Maybe obscure pokemon that don't get drawn much?

How about doing a furbait theme? Pokémon like Lucario, Gardevoir, Salazzle, Braixen, Zeraora, and Zoroark?
Let me know what you think.

at this point i always draw furbaits xdddd

The pokedex has fields for each pokemons bodyshape, you could roll a die and pick one of the shapes and go for that!

A male Pikachu having sex with a female Eevee, to celebrate Pokémon Let's Go.

Why not do some more muscular flamedramon with guilmon gay sex cuddles?

Greninja month. All Greninja. All the time.

Howbout those weird beta pokemon that never made it into gold/silver?

Go through the elements. Like fire types and water types.

How about "No Charizard Month"? (Pffft, just kidding~)

Serious suggestion though:
You could do stage-themes. Like, "First-Stage Month" with only unevolved first-stage pokemon who can evolve, "Middle-Stage Month" dedicated to pokemon who have evolved once and can evolve again, "Last-Stage Month" for only final evolutions or "Single-Stage Month" for pokemon who can't evolve and has no previous evolution.

How about some of the ultrabeasts?

Or maybe a month dedicated to one position, like sandwich position missionary ,mating press, stand and carry or dedicated to solo, duo or threesome

Maybe the regional birds? The Pidgey (maybe Spearow), Hoothoot, Taillow, Starly, Pidove, Fletchling and Pikpek lines?

Mythical Month!

How about a common pokemon month. Letting creatures like zigzagoon and rattata to get more art

Absolutely silly and stupid idea, but what about Pokemon with prime numbers haha?

A rock theme might be fun to try

Theme of horse pokemon, Blitzle, Zebstrika, Keldeo, Ponyta

Type advantage domination.

Whoever is being done or dominated has a type disadvantage to the one who's doing them.

Egg grouping

Hey two males can't produce eggs but they can try. <3

Pokefusions, Beta Pokemon or Fakemon.

Unusuals Pokemon (likely slugs, fishs and others not bipedal/cuadrupedal Pokemon)

A month of Pokemon that have something in common: All are based on some animal family such as reptiles or equines; who share one or more palette colors; or things like that.

Random selecctions, etc.

ese nombre xdddddd

Viste pa', la creatividad a full a la hora de elegir nickname.

I haven't actually seen Snivy anywhere in your gallery. Well, take it away!
Also, why not a focus on Pokemon based on a specific group of animals, like dragons or wolves? That might help.

Pred-pray if you haven't done that yet
Or natural enemies

Some joke ideas
Anything with magicarp
Ampharose and a "robot" like Pokemon
Genderless Pokemon that arnt legandarys

How about Pokemon that are inherently big or threatening but really just want to cuddle. For example: Tyranitar, Golisopod, Armaldo, Scolipede, and Golurk just to name a few.

I would call them "Big Softies". But hey that's just me.

We need more Muk art. id like a Muk/Male Trainer pic.

What about the quadrupedalism x biped month??? (that name sounds really weird lol)

Mega Pokémon is a nice idea, what about a month about prevolutions X evolutions?

You could do pokemon with their shiney version.

Shiny female legendaries and mythicals!

How about. . .

Pikachu clones (Marill, Pachirisu, Emolga, Togedemaru, etc.).
Single-gender Pokemon (Kangaskhan, Salazzle, Braviary, Gallade, etc.)

Dragons!

How about "perfect match"

Royals: Nidoking ♂ + Nidoqueen ♀
Bovines:Tauros ♂ + Bouffalant ♂ + Miltank ♀
Equines: Zebstrika ♂ + Rapidash ♀ / Mudsdale ♂ + Keldeo ♂/♀
Cervines: Stantler ♂ + Sawsbuck ♀
Caprines: Gogoat ♂ + Flaaffy ♀
Canines: Arcanine ♂ + Ninetales ♀ / Houndoom ♂ + Mightyena ♂/♀ / Manectric ♂ + Absol ♂/♀ / Lucario ♂ + Zoroark ♂ / Stoutland ♂ + Furfrou ♀ / Lycanroc ♂ + Luxray ♂/♀
Felines: Persian ♂ + Liepard ♂/♀ + Purugly ♀
Ursines: Ursaring ♂ + Beartic ♂ + Pangoro ♂
Lagomorphs: Diggersby ♂ + Lopunny ♀
Crocs/Gators: Feraligatr ♂ + Krookodile ♂
Frogs/Toads: Toxicroak ♂ + Seismitoad ♂ / Greninja ♂ + Politoed ♀/♂