Found some interesting info on IGN. (Apologies if mentioned already, but all seemed new to me.)
"Considering battling wild Pokemon is a common method to EV train Pokemon, we asked if effort values and individual values (hidden stats in the core Pokemon games) would make a return in Let’s Go. Masuda said “we wanted to make it more simplified,” and to “please wait for more details.” We did confirm there will be some differences in how you level up, raise, and train your Pokemon. Experience will still be earned by catching Pokemon and battling trainers, but other details were absent.
Though Pokemon from Pokemon Go can be transferred to Pokemon Let’s Go as long as they’re of the first generation, Masuda and The Pokemon Company had “no comment now” when asked if Let’s Go will be compatible with Pokemon Bank, or if Pokemon from Let’s Go will be transferable to the unnamed core series title coming in 2019."
So looks like you just get Exp. from catching Pokemon versus actually battling. Talk about bland. And these might not be transferable to the actual main games from the looks of it.
"These special partner Pokemon will not be able to be evolved, but wild Eevee and Pikachu are available, which can be evolved. If you don't like your partner Pokemon, you can always send it to the box."
RIP any minor interest I had. No dressing up a Jolteon, Flareon or Vaporeon? The Evolution Pokemon can't Evolve?
"The Pokemon box in this game is different, however. You will carry the "box" with you in Let's Go Pikachu and Eevee, allowing you to swap out your party on the go."
So our party is essentially 36+ mons now?
"Version-exclusive Pokemon will exist in Let’s Go, like the many Pokemon games before it. Battling and trading are both available online and locally, but online ranked battles will not be available, and as for the Nintendo Switch Online service launching in August, Masuda said they "don’t have any plans to utilize the online service right now."
So....is that a yes or a no on online? I thought the Switch has no other online once the official service comes out, which is before this game comes out?