I would play this again if it was as simple as put the patch file on the memory card as your PSP just plays the UMD. I never hacked my PSP and am not going to now.
Either way, I'm not that interested in playing the game again. It wasn't that great the first time. I did'nt understand the story sure, but I doubt that's going to help the shitty rts and tedious battle system.
Hacking PSP is as easy as ever. Recent developments have allowed hackers to sign apps as legit, due to the "signing keys" being discovered.
Here's the current process for getting your PSP ready:
Upgrade to 6.60 OFW (the "final" version of PSP firmware released so far) -> Run 6.60 PRO-B10 (or C, whatever your choice) -> Done
This doesnt even flash anything, it's a temporary install. Once your PSP turns off, it becomes OFW again. You can flash it to be permanent, but in your case, you dont want that, and that's fine.