I've not used Eldegoss yet, but now I know how helpful it is as someone who picked it to start with - appreciate that! Though I also had no idea the game as a whole was this unbalanced. Not sure if there will be many major changes with it in the future, but right now, while I do like it, I'm not sure if I'll stick with it longterm.
It's really not all that bad, the balance was good imo, its not like enemies were suddenly unkillable just because they had a shield, and zapdos isn't an issue with good strategy.
Yes going for zapdos can turn a loss into a win, but it can also easily turn a win into a loss, if the whole team goes stupid, and runs in without finishing off the enemy, then
the opposing team can just sweep in when every one is low on health and take all the points. It has some nuance.
the main take away is if your team is playing well before zapdos appears, they'll most likely keep doing so afterwards,
and it won't be a problem.
and the item system is actually pretty great, I'd say.
Its not massively destabilizing, even after maxing them out, most of the buffs don't do that much by themselves, and none of it will make you invincible.
What I like about the item system is it offers players a way to customize they're preferred mon to suit their playstyle.
To me its no different then ev training is for normal game.
If you want your pokemon to be a bit tankier, you can do that.
If you want more damage or more speed, you can do that too.
Its easy to think they have a far larger effect than they do by just looking at the item numbers alone.
If you want to check it out, there shouldn't be too much of a reason you can't have a good time.
The most detrimental thing really is just unhelpful teamates but that's the same anywhere, I guess.