We have 20 stores to rob, but would it have killed R* to add in an interior of 1 of the large banks in Downtown Los Santos? We would only need the first floor of said bank, the rest of the floors can be unavailable.
But, walk in, with guns pointed, in a Bank with say... 3 fixed Security Guards.... and a Bank Vault in the back. Intimidate 1 Bank NPC behind the counter, in the same way the current Intimidate works in the Store Robbery function. Once you Intimidate the NPC, he/she opens the back door, and now you have to place a Sticky bomb on the Vault door. BLow it up, run inside, grab the loot, and run outside and make your getaway.
This is all done in free roam, just like Store robberies.
1) If you die with the money on you, you drop the bags of loot. Any player can kill you and steal it.
2) The only way to successfully keep the Money from the Bank, is to get into your apartment. This adds another perk to having apt's. It's required if you want the Bank robbery.
3) automatic 4 star wanted level, maybe 5?
4) Since there is only 1 bank, that means when someone robs it, you have to wait X amount of minutes before it's robbable again. Maybe once an in-game day, which is 48 real life minutes? or maybe once every 3 hours? You can change it.
5) Make the payout something like 20k? Since the bank is only robbable by 1 player every amount of time, it's not like the payout is too big. There's risk.
You have to run from players and cops..... and it would be fun.