I've enjoyed playing handheld games since I first received my Game Boy as a Christmas gift in the early 90's. As I've gotten older, I've found myself playing handhelds even more. There are plenty of good reasons to take up handheld gaming, especially the 3DS (XL).
First, I find handheld gaming to be far more conducive to an adult lifestyle -- it's not often I have time to sit down in front of the TV for several hours to play console games. Also on that note, handheld games tend to be shorter than most modern games, or at least can be completed sooner because I can make progress at a faster rate since I can play it whenever I find a spare minute or two. Handheld games have also come a long way since the early days and many of them are fantastic!
I never purchased an original 3DS after hearing many being somewhat unsatisfied with its design (the Start, Select, and Home buttons apparently felt cheap, and I heard the bottom screen would actually end up scratching the top screen over time). Once the 3DS XL came, my interest was piqued. By that time, many great games had been released as well. I also purchased a 2DS because it looked cool and, in truth it's kinda neat, but more limited compared to the 3DS XL. I also have a Zelda 3DS XL, but I can't bear to open it!
Welcome to the world of DS gaming! I think you'll like it here. Plus, it can never hurt to have one more 3DS out there to Streetpass!