Been around cash games and small tourneys long enough to hear every bit of table wisdom under the sun, and heaps of it is just noise. The stuff that actually held up for me was pretty boring at first - fold more junk pre, care way more about position than your cards make you want to, and stop treating one pair like it's a family heirloom.
Biggest shift for me was quitting the fancy stuff out of position. I used to defend the blinds way too wide because you feel priced in and you don't wanna get pushed around. Cost me stacks, simple as that. Once I tightened up there and started leaning on people more when I had position, my sessions got a lot less wild.
Another one I rate is learning who actually bluffs in your player pool... low stakes players, especially live, love a call and hate pulling the trigger big on the river. Took me bloody ages to stop hero-calling every line that looked a bit odd. Most of the time it wasn't some sick move, mate just had it. Since then I've been way happier folding decent-looking hands when the story makes sense.
And yeah, bankroll stuff is boring as batshit but it probably saves more players than any hand-reading trick ever will. If you're always taking shots after a rough arvo, the strategy side barely gets a chance to matter. Keen to hear what advice still holds up for you lot, and what old poker cliches you reckon belong in the bin.