As a cryptocurrency developer myself, one of the main guidelines for selecting algorithms was that the algorithm should be optimized for low-end CPUs... My coin can be mined with powerful Xeon CPUs with 32 or 64 cores, but it doesn't give more coins than solo mining on low-end CPU. Basically more powerful CPUs waste time finding even better solutions when less powerful ones only need to find one solution per block.

Having lower average block difficulty doesn't mean that already mined blocks are easier to replace in blockchain as rewriting blocks still need enough transactions or otherwise other nodes will just reject the smaller blocks.