Actually last gen didn't have much to offer with JRPGs. The "Tales of" series was great, but actually I'm not sure if they're worth getting a PS3 for unless you really like the combat system in Tales. I don't mind immersing myself once a year in a new Tales game, but I think marathoning the whole series might be a little too much.
Disgaea is a great tactics game series. The story can be a little ridiculous at times, but it's alright. Valkyria Chronicles was amazing, but you can get that on PC now for under $10 during a sale. I think I got it for under $6 during the Steam Holiday sales?
Anyways there were a few gems last gen that were worth playing, but honestly I'm not sure if they're worth investing into a new console. If you find a PS3 used for cheap then go for it, but actually you can skip last generation if you're only buying it for JRPGs.
The market has moved to the handheld platform so I think you'd get more of your money's worth if you invested it into a 3DS and PlaystationTV if you haven't played the Persona series since there are a few great JRPGs on there that are easily worth the $80 for the home console version of the Vita.
3DS plays DS games so there are ton of JRPG games you can play on that platform from the past 10 years... Even the 3DS alone has gathered a lineup of formidable RPGs over the past couple of years. Fire Emblem Awakening is awesome for RPG fans. It disappointed a few Fire Emblem fans, but I loved the game and am extremely excited for the sequel next year. SMT4 was pretty good. A little difficult, but a good challenge like the Soul series of games. Xenoblade Chronicles 3D came out today. That's a must buy if you didn't try it on the Wii. Etrian Odyssey, PersonaQ, Monster Hunter, Bravely Default and then you have all the fantastic Nintendo exclusive IP like Zelda, Mario and Pokemon to play around with.
You can buy a PS3 if you really wanted to, but I think you'd be wasting your time if you bought it just for the JRPGs that were originally released on PS3. Kingdom Hearts collection was good, but that's probably coming to next gen before KH3 comes out, FFX is available on PSTV, FF13 and Valkyria Chronicles are available on PC for cheap during Steam sales. And the other game series might be too niche for you since you said you weren't really interested in them.
Seriously though you NEED to try the Persona series of games. They look incredibly niche, but they are some of the best games I played in a long time and actually P3FES and P4G were the games that relight my passion for JRPGs after being disappointed by the last generation for so long. ALL ABOARD THE PERSONA 5 HYPE TRAIN!
Anyways if you don't buy a PS3 then buy a PSTV and play Persona 3 Portable and Persona 4 Golden on it. It's worth the $150 to play both of those games. But yeah I think you should skip last gen since it isn't really worth it. JRPGs on handhelds work a lot better since if you need to pause the game then all you need to do is put the system in standby then continue later. Handheld gaming was great during my college years and warehouse job.