I would get the Vita 1st before the Switch. The Vita is close to the end of it's lifespan, and in the NA, it's probably already there. If you get it now, you can still play it to it's fullest for a few more years before things start shutting down or no longer getting supported. Then the systems will probably soar in price, as will the memory cards and games.
Also, in a few more years, the Vita's graphics will look even more aged than it does now compared to the modern consoles and PC. Even mobile games on phones and tablets will catch up. It's better to just enjoy it now before you find it as a hassle to even play. Games are still coming out though, and if you like a series that's still active, your support and money will still probably go to sequels for that series.
There aren't too many gems on the Vita, or games that you must play if you own one, and no other system carries then. So you don't have to worry about adding too much to a backlog, and after you've played those games, you can say that you've played the best that the Vita has to offer, and feel proud. Off the top of my head, I can name: Persona 4 Golden, IA/VT Colorful, Gravity Rush, Killzone Mercenary, Uncharted Golden Abyss, Moero Chronicle, Deemo, Steins;Gate, Danganronpa series, and a few more. I know I'm missing some, and a few of these are also on other platforms or were remade for them, but they are probably the go-to games for the Vita.
I don't own a Switch, so I can't say much about that console. But it's a pretty new console, there's a bunch of stuff that hasn't been added that Nintendo says they will, like the yearly online system, moving saves, voice chat, etc. There's a lot that they also haven't talked about, like the Virtual Console. And obviously, it's best days are still ahead of it, which is something I can't say for the Vita. So there'll be a lot to wait for, especially with the Switch. I'm sure once more and better games come out, hardware revisions come into play, and newer accessories, that there will be new bundles and cheaper prices. But I don't think the Vita will ever go down in price, and will only become more scarce (at least in the NA) as time goes on.