Assuming I don't care about online/trophies, and assuming I want to run my backups off the internal HDD, what would be my best method of hacking my PS3? It seems that due to various different SKU's and firmwares out there, it can be difficult to get on the same page as others. So with the conditions above set, I should:
Get a bigger HDD
Install CFW correct? (Which CFW?)
And I'd assume the instructions for your CFW would tell you how to install your ISO's on the HDD?
The instructions for CFW installation is mostly the same for any model.
Some precautions are: turn off Automatic Updating, turn off your Wifi if you must, remove your Game Disc (They have a Ps3_Update folder burned onto them), and finally you should format the USB you use to decrease chances of data corruption when transferring it in Recovery Mode.
If you're really cautious about it, go REBUG 3.55.2 first then use a hombrew called Toggle QA, this will insure a lower chance of bricking when you update to the newer firmware.
You could also as the person you're buying from to update to CFW for you. What you want is REBUG 4.65.2. Also tell them to dehash it (They'll know what this means since they downgraded the console, using Toggle QA is essentially dehashing if you want to do it yourself.)
I'm also thinking to softmod my PS3 Slim, becase I want to play so many games. But if PSN server go down for the PS3 then I can not download patches for my games.
So I want to DL all the games I want and update them before the server are closed.
And I want to play PSN only games forever, and I don't care about online but sometimes I want to update my trophies
There are pkgs of game updates so you don't need to go on PSN for them, you DL from PC instead. It's faster than direct PS3 update and you keep the update on your PC if you need a backup.