(this ranking asumes you have none of these, i also added some besides the original options)
First are the 3ds and Vita, cheap, near impossible to get banned, large non-hb catalog, large hb catalog, powerful enough to emulate a lot of stuff, great controls, super portable.
Second would be xbox 360 or ps3 because of cheapness (at least in most countries, cuz here even used they are like 150 usd, and that is if the seller is generous), near impossible to get banned, large non-hb catalog, large hb catalog, powerful enough to emulate a lot of stuff and great controllers.
Third would be Xbox or Wii, cheap, impossible to get banned, large non-hb catalog, large hb catalog, powerful enough to emulate some stuff, ok controllers.
Fourth would be a Shield Tv, cheap (in most places), impossible to get banned, ok non-hb catalog, large hb catalog, powerful enough to emulate most stuff, ok controller or controller up to you.
Fifth would be a Raspberry Pi or a similar SBC, cheap, impossible to get banned, large hb catalog, powerful enough to emulate a lot of stuff, the controller is up to you, the portability is up to you.
Sixth would be a cheap pc (reffer to what i said at the beginning), 200-400 dollars, impossible to get banned, large non-hb catalog, large hb catalog, powerful enough to emulate even some of the systems earlier on this list, controller up to you.
Seventh is Wii U, it still somewhat holds up in price due to collectors, near impossible to get banned, ok non-hb catalog, large hb catalog, powerful enough to emulate most stuff, ok controller, somewhat portable.
Last is Switch, alright, hold you pitchforks and let me explain, it's among the more expensive ones on this list, ban risk is fairly high, large non-hb catalog, large hb catalog, powerful enough to emulate most stuff, the controller just breaks easily, fairly portable.
Android phones: i didnt know where to put this one, so it's unranked, but assuming you go for a 200-400 dollar goal (including a controller), they are impossible to get banned, a few non-hb titles worth playing, large hb catalog, powerful enough to emulate most stuff, controller up to you, and fairly portable
Going back to what i said first, this ranking assumes you have none of this already, in reality, you probably have one or more of these, its best to use what you have (personally, i wouldnt run hb on a switch, but its your console, do what you want), no one lives in the same situation, and only you know your budget, what you are running, how you are going to run it, where you'll be using it, etc, personally, i just have an n3ds for on the go, and a fairly expensive pc at home, and that's the setup that works best for me, might work for you, or it might not. This list is just my opinion, feel free to disagree with me.