Well I for one like many like playing games with actual buttons and not virtual ones on a screen so playing with emulator's on a tablet is a no no for me. Well I can see the potential of a dreamcast, maybe 3do or Saturn emulation on a Vita and that excites me. Owning a Nvidia Shield Portable myself I know what works and what doesn't on it and emulation like 3do or Saturn doesn't work as well as I would have wanted it to
True, just making a point that there are other viable options when you have to consider price. The Nvidia Shield tablet was more of an example and is significantly stronger than the portable, so the comparison between each other is slightly different. As you've mentioned in a later post, the external controller is a deterrent in getting a tablet, so I'll further elaborate on this point in a different direction with different devices outside of your Shield portable (even though the portable is stronger than the vita already...).
The memory cards on top of the already expensive outdated hardware is pretty poor on Sony's part, but there aren't many devices out there that could run as many indie games and console adaptations as the vita unless you've looked at the GPD Win and if the goal is basic games and emulation then the GPD XD is also fine. I have a feeling that the Android and Windows versions of emulators are more capable (with as much time as both operating systems have been out and will continue to be upgraded, the devs have more incentive with these systems than either the 3ds and vita) than both the 3ds and vita could be and with either a GPD XD (cheaper android device with buttons and has expandable storage via sd card) or GPD Win (more expensive Windows device with expandable storage) you're looking at systems where emulation and support are more viable (theoretically the dreamcast emulator should work better on your portable than the vita with the current support for the platform indefinitely).
I don't have to talk about native games on android in general...not really many games out there that I could care about outside of what can be emulated, and compared to the vita, most of the games are really lackluster in terms of length and plot, but it seems like you aren't interested in vita games anyways since you weren't interested in its library (you sold the device twice before??). But still...another plus for the vita in this regard. However for the GPD Win, there's Steam and plenty of other game options as well as the device being a lot stronger than the vita and has support for expandable SD storage. Sure, the GPD Win might be slightly more expensive, but when you stack a vita with the cost of memory cards and the couple of pricey games you might be buying for it (even during sales times, pc deals kind of steal the show) your investment is pretty solid with the GPD. Edit: Also...in this regard, all games are "cross-play" from your PC to your handheld in the way PS4 is to the Vita sometimes lol.
I'd also like to make a note on your virtual and physical button preference. As far as the button quality goes, yeah, no debates here... the Vita beats out the 2 devices I mentioned, but what about L2 and R2 support? Both devices as well as the New 3DS supports these type of buttons as well, while the Vita requires virtual buttons...unless you're willing to sacrifice a stick or the start and select buttons.
Edit: I'd like to point out that I do have the Vita, New 3DS, Shield Tablet, and PC to support these claims and personally use my vita often for portable versions of PS exclusives like the Ratchet and Clank series, Persona 4, and Gravity Rush...just wanted to voice an opinion since price and content availability is the topic aforementioned.
TL: DR Your Shield Portable is better than a Vita and a New 3DS for emulation, you should get a GPD win if you want more games than what is offered by all 3 platforms and for the best emulation. If you don't like the vita library, why buy another one? There are less buttons on the vita than the others. Damn, them vita memory cards are expensive.
Edit: thought I should add a TL: DR section since I wrote a long rant...