A common houserule, if you feel that 500 credits is too little, is to simply double that amount to 1000 credits. This provides enough starting money for a blaster and things like a medpac or tool kit, or a bigger gun (heavy blaster pistol or blaster carbine) to those characters who'd benefit from something like that, and still have a bit of money left over for heavy clothing, a comlink, and either an extra reload or a stimpack.
While Jay and Sam may very well intend for players to have to take on extra Obligation to get more than just a blaster and a couple odds&ends, not every GM likes the idea of it being forced upon their players. And some players would rather take the extra Obligation to get some extra XP than feel they were being "forced" to take that Obligation for extra cash, particularly if they came over from the WotC d20 games which started most PCs with roughly 2K credits to buy their starting gear (only Soldiers really needed the extra funding if they wanted good armor and a rifle).
One other suggestion that came up during the early days of the Beta testing, before the starting credits was clarified, was to take a page from the old WEG system and simply assign characters the type of equipment that would make sense for them. A bounty hunter would have a blaster carbine, a padded vest, a grenade or two, a comlink, an extra reload, and a couple of stimpacks, while an outlaw tech might have a heavy blaster pistol, a datapad, and a tool kit. A smuggler would probably have a heavy blaster pistol, a comlink, a datapad, and heavy clothing, and a diplomat might have a light blaster pistol, some heavy clothing that's probably of better quality than the norm, and a decent stockpile of credits. While this approach is fairly free-form, it does have the problem of leading to an imbalance in starting equipment for some characters, as some PCs might have a greater amount of material wealth.