Lately, I keep hearing people talk about block builders, bundles, making it seem like if you don't understand, you can't trade properly. To put it simply, retail traders only need to know this: your submitted transaction might not be included in the block in the order you clicked the button; it could be bundled, front-run, or inserted somewhere, so don't blindly trust "setting slippage/limit orders will keep you safe."

My own approach is very simple: split large orders into smaller ones, avoid rushing in when liquidity is thin, and when I see large transfers on-chain or hot and cold wallets moving on exchanges, I don't immediately interpret it as smart money; I just treat it as noise and first look at where the liquidity exits.
I don't want to swallow all the complex stuff; I see complexity as an enemy, and I simplify whenever I can.
Anyway, I don't hold full positions, so I can keep a calmer mindset.