Huh?

Kazari, Uva, Medusa (because she is beautiful), roshuo, heart

Saeko Sonozaki/ Taboo Dopant
Heart
Medic
Kouhei Hayami/ Libra Zodiarts (Tuxedo Garren-sama bonus)
Mezool

Sorta kinda ranking-ish.

Heart(not until i saw ep 38)
The Original King from Kiva
Amadum
Tennouji
Reiji Nogi

1. Kirihiko Sonozaki
2. Daido Katsumi (Kamen Rider Eternal)
3. Ryubee Sonozaki
4. Shinkuro Isaka
5. Dr. Maki

The question was referring to the shows after Decade xD
If we go pre-Decade, it's a bit harder to say because those shows often lack clearly defined villains, but I'd say out of those...

Maya/ Pearlshell Fangire
Isaka/ Peacock Undead
Bishop/ Swallowtail Fangire
Smart Lady
N-Daguva-Zeba

In no particular order: Isaka/Weather Dopant, Captain Nira, Fueki, Ryouma Sengoku, Incompetent Scumbag Mitchy.

I would go Shinkuro Isaka, Ryoma Sengoku, Katsumi Daido, Kiyoto Maki & Mitsuzane Kureshima. No ranking, just these five.

Honorable mention for Phoenix, for a great setup that was totally wasted. Like many things in Wizard this could have been truly great.

Gamel/Mezool
Dr. Maki
Bishop
Sagittarius
Kaito

Top 5 post decade villains in no particular order.

Ryouma Sengoku, the most thugging scientist.

Phoenix, one of the best things of Wizard until his end.

Nira Mitsuhide, the pantomiming scumbag.

Dr Maki, fits well with the themes of OOO.

Isaka, really creepy and had great fights in his dopant form.