So if 7500 satoshi is a fair amount of coins to have in the future, I can be considered retired.
well, first of all the data is theoretical and assuming bitcoin becomes world's most influential currency, this may or may not happen, and even if it does happen, it will likely take another 10~20 years. (for full maturity, it's still entirely possible for bitcoin to become worth $100.000 or so within one or two years, in the most positive scenario)
secondly, 7500 satoshi are fine for the bottom 20% of humanity, and are a vast improvement compared to the bottom 20% nowadays, but still you wouldn't be able to stay on par with western standards with just 7500 satoshi. To be safe i'd try to be at least in the middle class range, if you can.
Note that 80% of the world population lives on less than 10 dollars a day ($3650/year) The bottom 20% currently lives on about $1.25/day (456.25/year) (in fact i get more than that on student grants alone, per month!)
The distribution i predicted is less harsh for the poorer people of society, the wealth distribution is much more even than the current distribution, because bitcoin does not rip of the poor nearly as much as fiat does, however, poor people will still exist even with bitcoin, it will just be a little more acceptable for them because they can now engage in global economic activity without having to pay huge fees to western union or banks, or even having no bank and/or not even having the option to sell their labor to the international or even national market.
The best thing is, the poor people will be able to become much richer by providing interesting goods/services to the rich and the only 3 things they need is:
1) Creativity (offer something that does not exist yet in europe/america, but is interesting for us to have)
2) Internet, to promote your product internationally
3) A bitcoin wallet, to accept payment
Rich people (people with many bitcoin) will probably look for such novelty items (or services) just for the fun of it, and the poor people will be able to make himself a little richer by it. The gap between poor and rich will slowly start to fade.
Compared to todays standard, the people who have 7500 satoshi (assuming they either leverage some of their bitcoins by investing it into smart businesses or actually set up something of their own to generate some income) will still be better of than living on $1.25/day, but not so much better that they could survive in western europe with that amount of money.
That is the theory at least. The future may look different, nobody can know for sure.
It's just an indication that even tiny amounts of bitcoin may make you relatively (or absolutely) rich.