Well, personally in terms of treasures to focus on. The ideal goal after getting Roshi would be to pick up Edo Hashirama from the Great Ninja War treasure which is probably around 2.5k pulls or so. Not entirely certain on the exact numbers. Edo Hashirama and Kurama Naruto are two of the most used characters still in China IIRC as far as treasure characters go.

In terms of event only characters. Try to pick up Edo Hiruzen, in fact I strongly recommend it. Of course the choice is up to you either way.

As for the Five Kage treasure, you could probably put some focus here I suppose if you really wanted to, but Ay 4th Raikage, and Susano'o Sasuke won't shine as well as they used to until Skill Experiment. Not suggesting at all that they are bad, it's just they are being out performed mostly by Kurama Naruto currently.

Anyways, I hope this helps.

P.S. Try to save up 300 Seal Scrolls always before using them and make sure to utilize the Ninja Recruitment events. Good way to gain some ground with a good chunk of additional pulls.

Personally I think you should go for gwn it have really good ninjas and in long run if you manage to get the super rare kurama or madara pays up big time. As far as the events ninjas goes its up to you rly. Depend what you want to play. Blitz, control, posion/ignite. Would recommend go for edo deidara since he is a standard and can be used everywhere. Sage, gnw matsuri etc.

after going for roshi, i'd reccomend for gnw(with the full 300 seals in the seal rebate) to eventually get edo hashi, which is still popular in cn. DON'T go for edo minato, he svcks, his damage is little, his mystery has a 3rd cooldown, and he has no scaling. I'd recommend the other 2 minatos.

EDIT: proof his damage is low

https://www.youtube.com/watch?v=qx8G8M9YBdc watch the first fight closely, his edo hashi did more damage in his lineup compared to edo minato who is probably stacked due to him being pos 1, and the damage edo minato deals is low. If you're a fan of minato, i'd suggest picking up HK minato, or jonin minato(he'll be really good after the bond update plus the release of 5 kage madara.

Like everyone said, go for GNW. No one in China uses the edo jin from those treasures as part of their main teams as there are better ninjas they can choose from.