The PvP Announcement

People like fun things, which should be reason enough for them to include it.

Limitations would definitely need to be set. A switching cool-down or even limiting the number of switches per battle would be one method of keeping fights form becoming stall-sessions.

Even with the simplified mechanics of Go, raids are much easier to optimize for over PvP battles. You know what the target is, you know how much you need to power up your squad, you know what specific set of moves to give your team to fight it - at most, you need to watch out for a specific moveset.

PvP has different variables in play. Did you know, for example, raid bosses have lower base stats than normal, barring the obvious HP? In PvP you're fighting against opponents at full strength. You thought Blizzard Kyogre hurt now? Better brace your ass when there's an extra 65 base points of attack behind it. On that topic, it invites people to play with different moves to wreck more optimal counters. Maybe there will be a prestige-like system, where the bigger the CP discrepancy between you and your opponent the better the rewards should you come out on top.

I think that (read: hope that) PvP will shake up the combat system. I think either way people will still do it. People had similar critical outlooks about trading, saying it "served no purpose" yet with introductions of things like bonus candies and lucky chances they've found a way to keep people involved with it. While I don't know what exactly they'd do, they'll likely do something similar to keep people battling.

First, I completely agree with you I do hope some more mechanics goes into battling in the future.

Second, I think it will be a lot of fun. 2 years and there was nothing to do with pokemon go in your house except for the IV checks. Now with trading I invited my group over to my house for a Trading night during this event. It was a lot of fun! I bbq Ribeye Steak and my friends brought sides, Warsteiner and a bottle of Single Malt Scotch. We traded for hours and got a lot of lucky pokemon out of it. Now that PVP will be coming out I believe I would do that again. I have a smart TV so i could connect their phones and we could all watch the battle go down. I'm glad that they are introducing aspects to the game where we don't always have to be on the go.

Tough to get players at the same account ability, but you could do what these T3 challenge/draft raiders do...lower player uses everything, 35mil XP player must include Shiftry, Ludicolo, and Wigglytuff in their battle party (or something to that effect)

It will be a completely different meta than raids. In a last man standing fight tdo is going to be more important than dps. When your opponent can dodge and not as predictable as AI, dodging skills will play a crucial role in determining the winner (assuming lag won't ruin the whole experience). So you would value more hard to dodge multi bar charge than slow 1 bar moves. I think if implemented right, it will be fun even with the simplified battle system we have now.

"Niantic's said they'd add PvP by years end"

they only said they want to add it by the end of 2018. that could easily mean it comes out in March of 2019. or June of 2019.

If its fun I ll do it regardless of rewards but I dont see it. Either it gets a crapy swipe and change fest or it will be not real PvP where a guy attacks and KI takes control over the other team (like we see in other mobile games) and you win every time as attacker.
Only way its gonna be fun is if they make it like in the original games.

There's a fair likelihood that some changes will be made to battle mechanics before or when PvP is launched. What those changes will entail (or if they will happen) is entirely unknown, but I'm betting on something changing and restrictions being in place for PvP battles.

That said, next to trading, PvP is one of the biggest features players have been wanting since the game's inception. There are likely going to be badges and research tasks associated with it, and potentially rewards for winning matches as well. Most importantly, it's going to provide an element to the game that's been sorely missing for 2 years and will shake up the meta even more in terms of what Mons and movesets are relevant. Blizzard Kyogre, for instance, will likely be a beast in PvP. Ho-Oh, who's been mostly underwhelming, will potentially be a solid option in PvP with solar beam. Even some of the tanky legendaries that currently don't have much use beyond Dex entries might find their niches in PvP battles, depending on how the system shapes out. In the current raid-centric meta, yes, most mons have movesets that are statistically superior for what you want them to do. This means that matching STAB moves that complement the Mon's typing as a specialist attacker are usually preferred. In PvP, this may not always be the case and people will have to think about whether they want their Kyogre, for example, to know hydro pump so it can function as a water-type attacker, or blizzard for counter coverage. Most mons have counter-coverage moves available, and I think they're going to become much more viable in PvP matches.

To top it all off, unless Niantic royally screws it up, PvP is going to be a lot of fun. My local Discord communities have already been buzzing with hype over it, and several people are already discussing potential future PvP challenges, tournaments, and contests.

TL;DR: PvP has the potential to do wonders for the game and, if done properly, give the game the element it needs to ensure it's longevity.

Under the current system, even with exactly the same team, an iPhone X user would have an easy win over an opponent using an old, low-end phone.

Considering the current battle system, I don't care about PvP. At all. Maybe when it comes out I'll change my mind, but as a concept, I simply don't care about PvP. I don't see how it could work with the current system. I'm not even sure how fun it would be - after trying to get to 2000 Gym Battle victories, I've decided that it's just too boring and time consuming for me to go for 3000. Raiding isn't that fun either because I already know before I go into a Raid that I'm going to win - the question is will I catch the Raid Boss and what Rewards I'm going to get. (The last Raid I lost was a Jynx raid I did when I just said "I'll do this one now." and didn't do any research at all. I screwed up badly and didn't win.)

If there is a major rework to the Battle System, I might be interested in PvP. But if it turns out to be "Choose Pokémon. Tap-tap-tap until you win or lose. Repeat.", then I won't be interested in PvP.