T4 Build

It depends what build you want and what you do on the app

If you war a lot it's beneficial to have a strength heavy build
If you party more it may be better to have an intel build

If you want to do both then have an even or close to even build

There is no best build. Try a build out and if you like it when you move into t5s keep it the same, if not try a new one out

 

Also most players find it's quickest to only upgrade t4s to level 2 to maximize plunder

 

Couldnt hae said it better myself

 

If you do system wars get balanced build, don't get strength as that means you're an easy cow  but build doesn't matter much at T4, only when at T5 should you determine your final build.