PPS 4% fee has an upper limit of 96% PPS payout
PPLNS N% fee has an average expected payout of (100-N+0.4)%
i.e. no upper (or lower) limit.
PPS pays independent of if you do anything useful for bitcoin.
PPLNS pays pool miners each time one of them does something useful for bitcoin.
The lower the fee on PPS the higher the risk of the pool going bankrupt - but it always has that risk.
PPLNS doesn't have that risk.
...
What am I missing here? Basically if you mine at a 4% pps pool or a PPLNS pool that have 96% luck history you get the same. right?
You are missing understanding BTC statistics.
Luck History has no effect on the future.