I get that feeling. There is a lot of creativity out there.
One reason why a lot of OSR/NuSR tend to be fairly conservative stems from a desire to remain mutually compatible among the wider B/X & OSR ecosystem of games, particularly modules and adventures.
If you like (5e) D&D style games but want to expand your tastes out a bit, there are some decent systems to try.
- Fantasy AGE (Green Ronin): It's a 3d6 game with a unique stunt point mechanic. Four classes. Talents. Specializations. Thematic spell groupings using spell points and checks. It's fairly familiar stuff. Second Edition just came out a month or so ago.
- Shadow of the Demon Lord (Rob Schwalb): It's like if D&D 5e and Warhammer Fantasy RP had a lovechild. It feels like Diablo as a tabletop game. Schwalb worked on the 5e design team, and he put some of his ideas that didn't win out into SotDL (e.g., Banes/Boons instead of Advantage). It's pretty dark fantasy with some gruesome and mature spells. There is a more Greyhawk-inspired fantasy version - Shadow of the Weird Wizard - but the Kickstarter for that has been delayed to fall of this year. But it's pretty easy to take the grimdark options out of it. It uses a milestone level progression that amounts to "you gain a level when you complete the adventure/module."
- Forbidden Lands (Free League): It uses Free League's in-house dice pool Year Zero Engine system. But it has an OSR feel with a flatter progression that leads to old school stronghold-building.
- Worlds Without Number (Kevin Crawford): It calls itself OSR, but its use of skills and talents make it unusual. It's really more of a mix of D&D B/X and Traveller, as it uses 2d6 + Stats + Skill Level for most skill resolution, though it still uses d20 + Stats + Skill Level for Combat. It has small set of classes - Warrior, Expert, Mage - that can be taken as single classes or mixed as half-classes and with specializations (e.g., necromancer, bard, healer, high mage, shapeshifter, etc.). The base game is free. There are more specializations in the paid version and in the Atlas of the Latter Earth book. Great advice for running sandbox games and world creation.
- Index Card RPG (Runehammer Games): It's a stripped down version of D&D that implements house rules and mods from YouTuber game designer Hankerin Ferinale. First Edition is classless and uses loot-based progression, including spells. Second Edition moves back to classes with some vertical progression mechanics.
- Cypher System (Monte Cook Games): a fairly traditional game with some narrativist elements. The GM side of things basically amounts to picking a number from 1 to 10 for a difficulty, multiply by three for the Target Number for players to beat. Player side amounts to skills, effort, and abilities to lower the difficulty before the roll. Players also create characters by picking a Descriptor, Type, and a Focus to create a mini character description: e.g., "I'm a Clever Warrior who Focuses Mind Over Matter."
- Fabula Ultima TTJRPG (Emanuele Galleto): an Italian TTRPG inspired by JRPGs built on the basic resolution system from the Japanese TTRPG called Ryuutama. It takes some cues from games like Fate, Cortex, Blades in the Dark, and Apocalypse World. But it's still a pretty traditional game underneath. Multiclassing is pretty much required as you are building your character from job ability packages.
I hate to be pedantic, but you literally replied to me with the list and not AbdulAlhazred.
Also, as (hopefully) a brief aside: You call yourself an OSR enthusiast in your description. I don't doubt that, but I am curious about what OSR games you like.