Just expand the current studios like they are already doing.  But next gen when they can make games for both platforms at once they will be able to create a lot of good games.

They never really "acquired" Rare per se, they had a partnership in which Nintendo had a 49% stake ... 

As far as "greatest" studios go we all how Rare is doing now and it's not like Monolith is making Nintendo a killing when it comes to revenues or profits ...

Nintendo has bought 10% of the shares in DeNA ...

I never mentioned Rare.

And I was talking about game quality, not revenue. ;)

Nintendo could probably build a few studios to make new IPs for the price of acquiring an existing one with decent IPs.

Oops I miss read that ... 

I'm pretty sure that Nintendo's own internal developers have made more quality games than Retro or Monolith's lifetime so far ...

I don't really think the answer is to pull a 'Disney' and go nuts & purchase all these studios, rather than to expand upon the ones they already have.
Particularly EPD, Monolith Soft., and Retro.
Compared to.... say Naughty Dog, who currently has 300 employees and they put games out at a relatively good pace. Last of Us was 2013, and Uncharted 4 is next year. That's a 3 year gap between games, pretty reasonable.
Now look at Retro, which is around 100 employees, DKC Returns and Tropical Freeze had around a 3 year gap as well. Pretty reasonable, however there have been demands for years about them doing Metroid, or a new IP entirely. But if they were to grow around the same size as Naughty Dog, they'd be in a better position to put out 2, maybe 3 projects that can be DK, Metroid, and/or a new IP.
As for Monolith, seeing as how long it took them to make X after they finished development for the original Xenoblade Chronicles, it could be another 5 years before we get Xenoblade 3, or whatever new game they come out with on NX, which would be well into its life cycle at that point, and right now Monolith sits at 123 employees (as of last year, I'm going off Wikipedia). Having double the staff could lead to them putting out these gigantic, groundbreaking RPGs a lot faster, and could enable them to grow into Nintendo's BIGGEST asset outside of the Pokemon Company.
And EPD, which has merged EAD and SPD together, means that they've got far more developers working together one multiple projects, which should lead to faster development. A good first step, but I think that adding an "EPD Group 2" to go along with Group 1 could go a very long way into shortening development times and increasing effectiveness when it comes to releasing and making HD games.

That's really what I think they should do rather than try to buy out any 3rd party companies... Although I wouldn't be against them buying Intellectual Properties, like say... cough*Sonic*cough.

And to think:
If they were to expand many of their development studios to both decrease development time and increase software output, ALONG with the potential, most likely idea of NX being one hybrid console-handheld platform.
All of those expanded, bigger studios would only have to concentrate their all their efforts and resources on one platform, rather than divide and seperate them into 2 different ones, which had led to all the software droughts we've seen from the Big N this generation, ESPECIALLY on the console side.
Doing all that could wipe out the software drought problem almost entirely.

Well, a lot of them have been around since the 80s so they've had more time to make great games. ;)

Purely in terms of the quality they're capable of, I'd still comfortably rank Retro and Monolith as among Nintendo's most talented studios right now.

They should have bought Atlus when they had the chance. Now they'll have to wait and buy Sega whole.

Rareware. C'mon MS cut bait and sell.

I've been saying for quite some time that Nintendo should buy High Voltage Software. They suck when it comes to art direction, gameplay development, etc... but their engine development skills are exceptional, considering what they were able to achieve on the Wii with their Quantum 3 engine (in terms of raw graphical technology).

So they should buy HVS, and get them working on a new engine for NX. As for their game-development, arrange some more capable developer, maybe Retro, to oversee it.

Other than that, Sega/Atlus is the natural choice for a publisher acquisition. Sega has some IP that would blend nicely into Nintendo's existing IP set, and also some IP that are very un-Nintendo. Atlus mostly has un-Nintendo types of IP. So acquire Sega/Atlus, and then do a bit of rearranging. The "Atlus" brand would hold the "mature" type titles that are dark and gritty, the "Sega" brand would hold titles that are more in the "cool" range (edgy, but suitable for a wider age range), and the "Nintendo" brand would hold titles designed to appeal to everyone.

Koei/Tecmo is an interesting possibility, but I'm not sure they'd gain enough from it. Other than Sega/Atlus, Nintendo would be best-served by acquiring a western publisher. Perhaps Zenimax?