Stats

I don't advise focus too much on stats becaus it depends what u have at the moment, means u can just run sim in top gear or stat weight  and u'll see what to eq or that stat combo on items to have. Keen in mind from leatherworking and jewelcrafting u can get items with any stat combo what u need.

Do i need to make any stat a bit higher and lower this one?
- It's just better to use the simcraft to sim yourself in raidbots in option "top gear" if you have questionable items in your bags. Sim will show what is upgrade or downgrade for you.

Is there a any cap for havocs?
- No. Read above.

My stat weight:
https://www.raidbots.com/simbot/report/nvfEnNBr9c2m4uXthENnJ5

Some more info about havoc stuff u can find in the my discord https://discord.gg/MzcsvqD