One thing I'd like to mention is that the concept of namechanging makes it impossible for people to not have a lot of money. If all of a sudden you want to namechange and RP a hobo, no one's gonna force you to just /charity your money away, and let's be serious here -- no casual player would just give away their money (or any other script-wise assets for that matter) for some extra immersion. Just saying this in case the whole "people carry a lot of money on them" thing is addressed in the future -- even if a "solution" is found, namechanging would still make it so that people have plenty of money (e.g. in their banks, houses, etc), regardless if they actually want to RP having that much. Also, keep in mind that no SA-MP RP economy can be kept perfect forever, so the amount of money people have at their disposal is bound to increase eventually to large numbers -- there are ways to keep everything in check, but again, nothing's perfect.
So, yeah, people having lots of money on them isn't something that can be "fixed"" overnight, although if I have to be honest it's not a huge problem. It requires work on the script though, that's for sure, and even if it is indeed addressed one day, then that wouldn't mean it's 100% "fixed" once and for all. We'll have to wait and see.
