I'm currently mainly using a mix of mainnet and L2, to put it simply, it all comes down to two things: whether this operation is worth paying more gas for "certainty," and whether I will be interacting with it frequently. For everyday small transactions and trying out new protocols, I usually go with L2 because it's cheaper and more convenient; but if I need to make a larger move and plan to hold for a while, I still prefer the mainnet, even if it's more expensive, for peace of mind.

Recently, I've been staking, sharing security, and stacking yields, and getting criticized for "copying" or "cloning" the strategies, which I can understand... The returns look quite attractive, but the layered approach means you don't even know where the risk might leak out when something goes wrong. My own compromise is: on L2, keep stacking and chasing hot trends to a minimum; on the mainnet, only do the simplest storage or asset swaps, and don't let the small savings from better user experience get lost back into complex structures.