It’s all about awareness. Reality checks are great, but they don’t matter at all if you’re not processing them. I’ve had reality checks in dreams that passed because I expected them to pass.
You are spot on about needing to go to fundamentals. Working on dream recall and journaling is great for two reasons. One, it suuuucks to have an LD and then forget about it. I’ve got a few like that. I remember them being awesome and then literally nothing else. Two, it makes you think about dreams more. The more you’re thinking about it, the more you’re likely to be questioning if you’re in a dream.
Awareness and expectations are next. I have a couple of articles I wrote years ago I’m going to share. They sum it up better than I can do in a single post. Make sure you read the discussion threads too; lots of good feedback from long-silent accounts.
I still have the most success after having already slept some. I’ve never done the full WBTB where you get up for an hour. I can’t fall asleep after that. Just long enough to shut off my alarm or maybe go to the restroom. Lately I get the best results if I take a nap in my early afternoon. Very vivid dreams which makes it much easier to realize I’m dreaming (and they’re a lot more fun).
Finally, learn to enjoy your ND’s. I can’t think of anything less productive than going “ah man, I didn’t get lucid.” For me that change of mind really helped. Every night I had unique experiences instead of every night feeling like a failure.
Good luck, and stick with it.