I would love to upgrade to a New 3DS or an XL model but it's not really in the cards for me right now since I'm saving up for a Switch. But I do agree that a 3DS is definitely the system to own if you're in to portable gaming. It's the first time in my life where I have enough time alone to actually play games on my TV (I share it with the rest of my family and gaming is pretty low on their priorities list), so I grew up playing portable games almost exclusively. I owned a Wii, Wii U, PS2, and PS3, but they never got much use. And to be honest the only game I play on my PS4 Pro is Persona 5 but I anticipate getting more games like A Hat In Time and Ni No Kuni 2 when they release, and I think that will up my usage of the console a lot. I still use my PS3 a lot to replay Okami and Ni No Kuni, but I still use my 3DS and Vita a lot. And my Vita is basically just a Persona/Dangan Ronpa machine so I ony use it when I'm in the mood for those games. So the console I get the most use out of is my original 3DS. It plays all the DS games I grew up with and all the 3DS games I learned to love during my teenage years, and all the 3DS games I love now. I'm currently replaying through FE Fates: Conquest and considering taking the plunge and buying the third route who's name escapes me at the moment. I just know I can't play Birthright, siding with Hoshido seems so wrong to me. But there are just so many fond memories on my 3DS. Having a 3DS is actually something that really saved my life. I was having a tough time in life and I had quit playing games for a few years but my parents bought me a 3DS anyway because they thought I would still use it. It ended up sitting in my closet, until one day I was browsing youtube and saw a trailer for Pokemon X and Y. I had never played a Pokemon game but I collected the cards as a child (I had about 800 cards by the time I was 9). After caving to some peer pressure I sold them all which really I think was the start of my dark period as a tween/early teenager. Anyway I saw the trailer for X and Y and something just clicked. It wouldn't be coming out for like a year and I just couldn't wait. I spent all my money on a copy of Black 2, the Pokedex/Player's Guide, and a new Pokemon themed carrying case for my 3DS. The 2 days I spent waiting for it to arrive were agony. But the moment it came it consumed me, I ignored homework and basically everything else for 2 days and beat the game. I quickly moved on to playing White and finished that just as fast. My new found love of Pokemon lead me to start playing competively, drawing fan art obsessively, and even becoming a mod on a Pokemon forum. I had never felt so happy and fulfilled in my life, it's kind of crazy. And when X and Y did come out, it only amped up my enthusiasm. I wasn't as crazy about Sun and Moon (haven't beat either yet), but my love of Pokemon remains and I owe that all to my 3DS.
Besides that some of my all time favorite games are on that console. Bravely Default, Persona Q, Mario Kart 7, Animal Crossing: New Leaf, Luigi's Mansion: Dark Moon, Fire Emblem Awakening and Fates. And it lets me play all my favorite DS games from my childhood: Kirby: Squeak Squad, Pokemon Mystery Dungeon: Blue Rescue Team, Cooking Mama, Mario Kart DS, the recipe games, Super Princess Peach, Mario Party DS, all of the Ace Attorney games, Nintendogs (the original), and Animal Crossing: Wild World (the only game I've ever used a Game Shark on). The DS/3DS shaped who I am as a gamer, determined what and how I want to play. I really have to wonder how different my tastes in and philosophies on games would be if I had grown up spending lots of times on home consoles. I probably would be more hung up on graphics and have longer play sessions. When it comes to games, to me stylized always beats realistic and bad graphics don't undermine a good experience. I also have gaming sessions that last anywhere from 5 minutes to an hour typically. I'm used to picking up my 3Ds doing a couple of battles or beating a level than closing it and switching to something else. I do a bunch of these mini game sessions throughout a day: during a meal, between classes, on break at work, waiting in line, going to bed, etc. I prefer long games, but I don't worry about them sapping up all of my time because with handhelds you can work them in to your day rather than setting out time for them.
Geez this was a long post for what was supposed to be a simple message. Sorry about that, but as you can tell, I agree that the 3DS is a must have system.