>>1241799The Aquarion trilogy, Flying Phantom Ship, the Eldoran trilogy (Raijin-Oh, Ganbaruger, and Gosaurer), RahXephon, 30,000 Miles Under The Sea, Hellhound Liner 0011, Astro Ganger, Brave Raideen, Zambot 3, The Robot Romance trilogy (Combattler V, Voltes V, and Daimos with Daltanious as a fourth spiritual successor), Daikengo, just about everything by Go Nagai (the six Mazinger movies from the 70s would be up your ally and yes both Gaikings are Go Nagai... which Toei stole from him), most Braves/Yuusha shows (not Goldran it's low quality), Neo Ranga, Dai-Guard, Big O, God Mars, Ideon, Dunbine, Primitive Boy Ryo, Gravion, Godannar, Olynssis of Silver, Danguard Ace, Sakugan which aired just last year, Unit Pandora, OZMA, Gunbuster and Diebuster, the Eureka Seven franchise (don't fall for the memes Pocketful of Rainbows and Astral Ocean are better than the first series), and Redline.
There has also been a lot of bad quality series featuring kaiju so consider this a "to avoid" list:
Listeners (very few anime fail this hard), Godzilla SP (worst in the franchise), Netflix Godzilla (catastrophic failure), Netflix Ultraman (beyond the slow and barely any action), Nanoha (lolicon garbage), Madoka Magica (also lolicon garbage but less blatant), Mai-Hime (the very first anime I thought "wow this sucked), Made in Abyss (it takes too long and the last episode was double length for no reason), Patlabor franchise (so much inconsistency), Xam'd (beyond the sluggish intensifies), Symphogear (the first three seasons kind of suck and it's one of those cases where it would have been better if it was a lot darker and more characters got killed off), everything from Studio Trigger (they can't make anything higher than a 4/10 and ruined Gridman), and Planet With (just badly made all around).