Bitcoin community can not just decide to divide further. For this new computers are needed or significant revamp of software. If you know anything about how computers works you know what a double is. The range for this data type is -9,007,199,254,740,992 to 9,007,199,254,740,992. Compare this to total number of allowed satoshis which 21,000,000,000,000,00 this is also 16 digits. So you can say that the number of satoshi is maximized based on the modern day hardware. I am skeptical that the latter is going to change by much in the coming years there is simply no need for that in mainstream.
I hope you're not suggesting to use a floating point data type for storing an amount of Bitcoins, because that's a really bad idea! Anyway, 64 bit fixed point data type allows for 3 more decimal places (2^64 > 2.1*10^18) so Bitcoin isn't maxing out the hardware - even if we do not change the width of the data type used in the current transaction format.