There is only 1 stat that is fondamental in this game, initiative. Owning better init means that you will have more chance to win. If you want to spend your money, probably the best way is to invest in advanced refines.

About ninjas, learn to invest smartly. Some ninjas like kisame 2.0, deidara 2.0, angel konan i.e. are still meta in china, so investing in them will give you more presence in gnw than a random orochimaru akatsuki, edo nagato or similar.

I can give you a list of my Favorite youtuber more or less active in CN server.

1) This guy is probably the best. He has 2 accounts in the middle of the power chart (200k) in CN. He also uploads the best fights in his Space time. (chinese)

2) She is your P2P, with over 350k power. Definitely not the strongest, but in her matsuri / bond videos you can see what the higher-than-normal power in CN use. (chinese)

3) Not the best nor the one i like most, i think he is one of the best to begin if you have no idea about CN. (english)

4) Just mute the video. He is a low power guy but sometimes his fights are funny. (chinese, mute the video)

5) He is Memo. So a bit between all of the above. (english).

There should be also somewhere in the forum a google doc on early and basic skillbreaks and another one about upcoming ninjas translated (care that there are some errors).