those who play on JP server how are you managing savage and others hard content ?

[Illmaeran]

Not using kanji is a dead give away so I'm not surprised you're seeing social issues where you are.

Mana DC has very few English speakers from what I've been told so you're probably better off moving to Tonberry (Elemental DC) or an NA DC. Tonberry the unofficial OCE/SEA server so it's got the largest English speaking population of all JP servers while the DC as a whole is still heavily JP slanted so you'll have plenty of opportunity to play with Japanese.

Something very important to keep in mind is the JP data centers have an established way of doing things and making public suggestions to do things differently is going to be received rather poorly. If you want to raid, learn the JP strategies and customs, and don't deviate from them. If that doesn't sound like your cup of tea, you'll be much better served going to NA.

As far as ping goes, I live on the NA East Coast and play on a JP server. While I don't play savage, I don't find the ping to be a do-or-die thing 95% of the time. I do get the occasional lag spike death and loading times are a bit long, but not unbearable.