Babel config for NodeJS 4.x

server.config.js

{
    compact: false,
    optional: [
        // 'runtime', // Don't use runtime, it's overabundant in case of Node 4 and bluebirdCoroutines
        // 'asyncToGenerator', // Use bluebirdCoroutines on server because we have blubird on server, not client
        'bluebirdCoroutines', // Use it for async/await on server-side instead of babel helper asyncToGenerator
        'es6.spec.modules',
        'es7.asyncFunctions',
        'es7.classProperties',
        'es7.comprehensions',
        'es7.decorators',
        'es7.doExpressions',
        'es7.exponentiationOperator',
        'es7.exportExtensions',
        'es7.functionBind',
        'es7.objectRestSpread',
        'es7.trailingFunctionCommas',
        'optimisation.modules.system'
    ],
    blacklist: [
        'es3.memberExpressionLiterals', // For very old browsers
        'es3.propertyLiterals',  // For very old browsers
        'es5.properties.mutators', // Enabled in V8 4.2 (Node 4)
        'es6.arrowFunctions', // Enabled in V8 4.5 (Node 4)
        'es6.blockScoping', // Enabled in V8 4.1 (Node 4)
        'es6.classes', // Enabled in V8 4.2 (Node 4)
        'es6.constants', // Enabled in V8 4.1 (Node 4)
        // 'es6.destructuring', // Still developing
        'es6.forOf', //  Enabled in V8 3.28 (Node 0.12)
        'es6.literals', // Numeric literals enabled in V8 4.1 (Node 4)
        // 'es6.modules', // Proposed
        'es6.objectSuper', // Enabled with classes in V8 4.2 (Node 4)
        // 'es6.parameters', // Rest in V8 4.7, Spread in V8 4.6, Default is still in development
        'es6.properties.computed', // Enabled in V8 4.4 (Node 4)
        // Shorthands Enabled in V8 4.2 (Node 4), but with 'async' babel handle them incorrect without this transform
        // 'es6.properties.shorthand',
        // 'es6.regex.sticky', // Proposed
        // 'es6.regex.unicode', // Proposed
        'es6.spec.templateLiterals' // Enabled in V8 4.1 (Node 4)
        // 'es6.spread', // Will be enabled in V8 4.6 (Node 5)
        // 'es6.tailCall', // In development

        // 'flow',
        // 'react',
        // 'react.displayName',
        // 'regenerator',
        // 'spec.blockScopedFunctions',
        // 'spec.functionName',
        // 'strict',
        // 'validation.react'
    ]
};

Notes: You can't use default parameters in arrow functions, if arrow functions are in black list, because babel use arguments to realize that default value needed. So you must use simple function in this case, until v8 implement defaults natively.
But you can use destructing for arrow function parameter and default values within it.