Intel smaller l1 cache issue

Cache alone doesn't guarantee performance. Intel spends a long time trying to optimize the balance between cache size, clock speed, and core capabilities to give the best overall performance. for a given die size, price, and power consumption.

they can put it into their flagship line, and increasing level 1 cache(not level 2 or level 3) simply wouldn't enlarge the die that much as put level 2/3 cache into the chip. if pentium m/core can finally increase their level 1 cache from typical 32k to presenting 64k per core for core2/core i7/5. why wouldn't they step foward? beside level 1 cache isn't consuming amount of power as level2/3 cache does.

just don't understand why intel rather putting more level2/3 cache instead of improve their level 1 cache size. it will be a huge performance boost. (like pentium m "dohan" to pentium 3 "turatin", at least more than 90% increase in the performance under same clockrate.)