A point worth discussing, and I see two ways to go with this:
- Embrace the nature of what it provides. MT!'s idea is perfect sequencing and ideal plays, since lines are straightforward besides luck you know exactly what can happen and how. Let's take a scenario: Lead Deoxys-Speed vs Lead Ting-Lu: something straightforward to think is that Iron Valiant is a good mon to switch into Ting-Lu, but not if they have their own Deoxys-Speed in the back, you risk your Pokemon dying right away. This is sort of how very fast and strong Pokemon self balance themselves, in this scenario they become a liability. Depending on team compositions a better approach than going Iron Valiant would be to go a bulky mon like Kyurem or Zapdos, that wins the 1v1 without getting instantly OHKO'd by something in the back. This can create a trade-heavy metagame that rewards good positioning and momentum the utmost, with players running into dead ends if they didn't have enough foresight. It's really hard to theorycraft so we'd have to see how it goes in practice
- Try to mitigate the perceived issue. My preferred idea is that slow switch-out makes the pokemon who is switching in act second in the next turn, no matter what. This maintains Pokemon's core lack of switch-in "safety", in that you are hardly ever able to bring in a threat for free and get a kill off it, but you instead have to work for it by getting your threat in against a Pokemon that cannot kill you, and that you can kill back. This can also polarize MUs by making it extremely more difficult to switch into a strong Pokemon, considering one Quiver Dance or Dragon Dance can have you completely cooked. I would say this more closely resembles how Pokemon is currently played, so it's an option worth considering.
- What the fuck is a speed stat?! Option 3 consists in calculating turn order at preview using the average speed of all Pokemon on the field, and maintaining that turn order for the rest of the game. This is a potentially gamebreakingly horrible option that I am including because I find it sorta amusing.
I don't skew too heavily one way or the other, I am a proponent of "the less rules you add the better" and I would like to see what option 1 brings in theory, but option 2 sounds like the more competitive option in my head.
I still think we could implement something similar to option 3 for deciding turn order: given that speed is very important in this meta and high speed mons are bound to be prevalent, this would sort of balance it by giving the slower team the advantage, counterpicking their lead. It would also help remove the potentially only 50/50 in the game.
The problem is the logistics of the implementation: say a slower Pokemon wants to use the move Protect, how do you make that happen. Do you give the slower Pokemon the choice to act first by using the priority move every time he's moving second, effectively broadcasting that they have a priority move and adding a plethora of empty confirmation turns in each game? Do you make it a "quick time event" by being able to click Protect in your opponent's turn if you're faster than him but making Protect counterplay be "literally just instaclick"?
Choice Items still have their drawbacks: a Choice Band Iron Valiant may click Spirit Break on your Great Tusk, but instead of being forced to go a faster mon that OHKOs, you can now safely go Kingambit, force them to switch out and kill something else entirely. Probably a poor example but you get the idea.
While theorycrafting with a few friends we also thought about negative priority moves like Trick Room and Counter. While technically you can just remove the priority from the moves, they can end up being overly broken as a result, so more discussion has to be done about that.
And yeah Focus Punch should definitely be banned, the alternative is that we have it work the same way it normally does, with it only attacking if you don't get hit in the opponent's next action, but that sounds sorta gimmicky to implement with slow focus punch and would also probably just make the move useless as a result. There's definitely other things that need to be looked at, like the ability Stakeout and moves like Eject Pack and Eject Button, but all in due time.