I don't think you understand how a calendar works. In the case of the past six months, that means primarily January forward, though if you want to count the lackluster December, go for it. Otherwise, let's see:
A Link Between Worlds: does not refute my point about Nintendo working off a template, nor does it refute the idea that they push out shorter, lackluster titles for the sake of closing gaps in their Nintendo-only release schedule. Even then, November last year isn't exactly recent.
Bravely Default: Only popular because there was literally nothing else worthwhile released on the 3DS for two months prior to its release. During a drought, even if the water is a little dirty, people will take it over dying of dehydration, so to speak.
Shin Megami Tensei IV: Last year.
Professor Layton and The Azran Legacy: Appeals to a very niche audience for one (as Professor Layton has from the start), and last I heard, even Professor Layton fans didn't find this one to be all that good. Not exactly a stellar example.
Rune Factory 4: Not only is this not from the last six months, but we will never see another Rune Factory game again. So, ya know, not exactly a reliable franchise, nor a good point.
Mario and Luigi: When did this one release again? Near the beginning of the 3DS life? Yeah, I thought so.
So, now that we've established that you have no understanding of how time works, let me further confirm my point by pointing you to this handy list that Metacritic provides that has every 3DS release of note on it, organized by date, from most recent to earliest:
link - notice anything interesting? How about the distinct lack of not only notable, but good content released for the 3DS since the start of 2014? There may be a couple of titles that are actually good, but of the handful, at least half have fallen short as not being good enough to warrant the purchase price, or even really a play through. You can't tell me this outdoes the Vita. You really, truly can not. You could potentially argue that the Vita is not doing better, but you can't say the 3DS is doing good simply because people blindly buy into it out of nothing but brand loyalty.
How about I now hit on how you cherry picked from my post to make your sub par argument? I named the good exclusive content from the Vita's about 1.2 years of life at this point. 1.2 years, and I was able to name more than a handful of exclusive, original content worth playing and owning. This seems to refute the argument of the fact that the Vita gets no exclusive content, no? It's not only exclusive content, but it's quality. The ports filling in gaps between exclusive releases does not hinder the Vita either. If anything, it strengthens the library by giving further access to PS1, PSP, and now even PS2 games right there on the Vita, on the go. Even five years ago, people would have done a lot for this ability, but it wasn't possible. Now that it is not only possible, but being enabled by Sony, we boo it and frown on it because, well damn it, Sony actually has third parties that want to work with them and that's a bad thing! Nintendo's lack of third party support isn't a strength. It hinders them, horribly, and leads to garbage like the latest Yoshi game out of desperation to get something, anything out there to clear up the sometimes months without any releases of any note. Are ports really worse than that? Really? Are you so blinded by brand loyalty that you can't recognize the shortcomings of the 3DS? Neither handheld is perfect, and acting like Nintendo is still a handheld king is just silly, as they're suffering as well.
As a final note, just to drive this point home:
the 3DS requires Nintendo exclusive content to survive. People
do not buy third party content 99% of the time when its released on Nintendo systems which is precisely why Nintendo systems have such a hard time getting third parties on board. In the long run, of course the 3DS will have more exclusive content because Nintendo almost exclusively keeps the system afloat. That doesn't make the number of exclusives impressive. If anything, relative to the amount of third party content, the amount of first party exclusives throughout the 3DS's life so far reeks more of desperation than of originality.
I will be the first to say that the Vita isn't perfect, but acting like it's doing something wrong just because it gets more ports than you get on your Nintendo console is really just dumb.